A cabling fixture attached to a wall in a work area for connecting computers to the network. Also called a faceplate.
How It Works
Wall plates can have RJ-45 jacks for 10BaseT networks (which resemble household RJ-11 telephone wall jacks), BNC jacks for 10Base2 networks, or SC jacks for networks that use fiber-optic cabling. The back end of the connector joins a horizontal cable that runs inside the wall or through a false ceiling or floor to a patch panel in the wiring closet for that floor. Computers are then connected to the wall plate by a short unshielded twisted-pair (UTP) cable called a drop cable. Wall plates typically come in mono-port, dual-port, and quad-port configurations.
Wall plates are an important feature of a permanent networking installation because they enable stations to be easily disconnected and reconnected to the network and they protect cables from damage. Flush wall plates are flat, like AC outlets, but angled wall plates are often a better choice because they offer better protection from excessive bending and from contact with heavy or sharp-edged furniture.
Graphic W-1. A flush wall plate and an angled wall plate.
NOTE
You can get special wall plates for serial interfaces that use DB connectors such as DB9 or DB25. These wall plates are used in mainframe computing environments in which dumb terminals are connected to mainframe hosts by using RS-232 serial lines.
TIP
Be sure to label or number wall plates so that you can easily identify the port on the patch panel to which they connect.
If you can’t run cabling inside walls and must instead tack cabling directly onto the interior wall surface, use surface-mount boxes instead of wall plates. These are box-shaped adapters that screw onto the wall and have side or face jacks for connecting cables.
See also premise cabling
See wide area network (WAN)
A communication circuit that joins two or more local area networks (LANs) into a wide area network (WAN).
How It Works
Many types of WAN links are possible between networks, depending on the networking protocols and telecommunications carrier services used, but WAN links can be grouped into three broad categories:
Circuit-switched services: Dial-up connections that establish a temporary switched circuit through the carrier’s telecommunications system for the duration of the communication session. When the connection is terminated, the carrier’s switches are freed up for other uses. One problem with this type of service is that the quality of communication varies between sessions with the quality of the switches and connecting trunk lines used. For this reason, circuit-switched lines are often used as a temporary backup link in case the primary leased line goes down. Because circuit-switched lines cost much less than leased lines, they are also used in low-traffic WAN networking environments. These lines are typically point-to-point connections, but they allow users to dial any connection they choose instead of being confined to a single connection, as is the case with leased lines. Examples of circuit-switched WAN links are modems and dial-up Integrated Services Digital Network (ISDN) links.
Leased lines: Dedicated connections that establish a permanent switched circuit through the carrier’s system. They are always “on” and ready to carry network traffic. Leased lines are typically much more expensive than circuit-switched lines because the carrier’s switches are dedicated to the customer even when they are not in use. Leased lines are typically point-to-point connections. A typical example of a leased line is a T1 line or fractional T1 line.
Packet-switching: Can be either dedicated or dial-up connections to a public packet-switching network such as X.25, a public frame relay network, or even a virtual private network (VPN) that uses tunneling over the Internet. The switches for a communication session are not configured when the session is established; instead, switches send packets of data along the best route possible by using the logical address of the destination node, which is contained in the header of each packet. Packet-switching links can be either point-to-point or point-to-multipoint connections, depending on how they are configured.
TIP
Leased lines are best for dedicated high-traffic WAN links, but packet-switching connections are often more cost-effective when the traffic is intermittent. It’s a good idea to use circuit-switched connections as a backup link for leased lines.
See Wireless Application Protocol (WAP)
See dense wavelength division multiplexing (DWDM)
See Web-Based Enterprise Management (WBEM)
See Wideband Code Division Multiple Access (W-CDMA)
See dense wavelength division multiplexing (DWDM)
See World Wide Web (WWW)
A collection of elements on a Web site that performs a task programmatically. Web applications are designed to run on Web servers (such as Internet Information Services) and use Web browsers such as Microsoft Internet Explorer as the user interface. Web applications are typically client/server applications. For example, the ordering mechanism on an electronic commerce site is a Web application. Web applications can be developed by using a variety of technologies, including the following:
Active Server Pages (ASP)
ActiveX components
Client-side scripting using Microsoft Visual Basic, Scripting Edition (VBScript) and JavaScript
Internet Server API (ISAPI)
Common Gateway Interface (CGI)
A proposed set of standards that enable computers and other network devices to be managed using a standard Web browser such as Microsoft Internet Explorer. Web-Based Enterprise Management (WBEM) is an initiative of the Distributed Management Task Force (DMTF) and originated in 1996 as a joint initiative of companies headed by Microsoft, Intel, Cisco Systems, Compaq, and BMC Software.
How It Works
WBEM enables information such as the amount of RAM in a computer, the capacity of a hard disk, the type of process, and the version of the operating system or firmware to be extracted from computers, routers, switches, and other network devices. This information can be used for detection of potential problems before they occur, for remote management using products such as Microsoft Systems Management Server (SMS), and for planning and other decision-making purposes. WBEM is designed to work in heterogeneous enterprise networking environments to collect diagnostic and management data relating to hardware from multiple vendors, different operating systems, different network protocols, and distributed applications.
Currently, enterprise-level network management includes using Simple Network Management Protocol (SNMP) for managing routers and switches, Desktop Management Interface (DMI) for desktop systems management, proprietary management protocols and systems for managing vendor applications, and so on. WBEM simplifies management by providing a common model and data source that can be extended to function with existing protocols, networking components, and applications.
The framework for this standard is the Common Information Model (CIM), a set of schema for cross-platform network management also developed by the DMTF. Once information is collected, it can be shared across an enterprise and displayed using WBEM management systems.
Microsoft has built the WBEM architecture into Windows 98 and Windows 2000 and has made it available as an add-on for Windows NT 4. Windows Management Instrumentation (WMI) is Microsoft’s implementation of WBEM for Microsoft Windows platforms.
TIP
WBEM 1.1 is included in Windows NT Server 4.0 Service Pack 4; you install it by running wbemcore.exe. It is not included in Service Pack 5, but you can install it from Service Pack 4 after you apply Service Pack 5.
See also Common Information Model (CIM)
An application that supports the client side of the Hypertext Transfer Protocol (HTTP), the Internet protocol for the World Wide Web (WWW). You can use a Web browser, also called a “browser,” to access (browse) content published on a Web server. This content can be static, meaning it consists of ASCII text files formatted using Hypertext Markup Language (HTML), or the content can be dynamic, meaning it is generated on demand using client-side or server-side scripting in languages such as JavaScript or Microsoft Visual Basic, Scripting Edition (VBScript). Web browsers typically offer additional features to make browsing the Web easier and more profitable. These features include the following:
Toolbar buttons for navigating forward and backward through the tree of previously displayed pages, for stopping the download process, and for manually refreshing a page that loaded incompletely.
Lists of favorites or bookmarks that store Uniform Resource Locators (URLs) of frequently accessed sites as well as tools for organizing and accessing those URLs.
Options for specifying a default home page from which to begin browsing, a default search engine for searching the Web, and other default browsing options.
Security options for handling such concerns as whether to allow scripts, ActiveX components, or Java applets to run on the browser.
Facilities for displaying the underlying source code or HTML of a page, and even for editing and publishing Web content.
Integration with other Internet software such as mail, news, or chat applications. Some Web browsers are packaged as stand-alone applications, while others are part of an overall suite of Internet tools that are integrated at various levels.
The first graphical Web browser was developed in 1993 by a group of students headed by Marc Andreessen at the National Center for Supercomputing Applications (NCSA). This browser was known as Mosaic and was distributed free. In 1994, Andreessen left NCSA to help found Netscape Communications, which developed the Netscape Navigator browser. The popularity of this browser helped foster the explosive growth of the Internet in the mid-1990s. Microsoft soon entered the arena with its Internet Explorer browser, which has become the most widely used browser on the market. Starting with Windows 95, Microsoft began closely integrating Internet Explorer into its Windows operating systems, with the result that users running Windows can access Internet resources as easily as files on their own hard drives.
On the Web
•
Internet Explorer home page : http://www.microsoft.com/windows/ie
•
Netscape browser home page : http://home.netscape.com/browsers/index.html
•
Mosaic home page : http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/
See also Hypertext Transfer Protocol (HTTP), Web server
Any technology that enables automatic delivery of information from Web sites on the Internet. For example, you might make use of webcasting to receive a weather report update every 10 minutes. An example of a technology that enables webcasting is the Channel Definition Format (CDF) technology included with Microsoft Internet Explorer versions 4.0 and later.
Webcasting in Internet Explorer 4 can be divided into three categories:
Basic webcasting: Any existing Web site can be enabled for webcasting without modification to the site format and content. Internet Explorer can be scheduled to “crawl” the site at scheduled time intervals, check for new or updated content, and notify the user of this content or download it for offline browsing. This process is called “subscribing” to the Web site.
Managed webcasting: An ordinary Web site is turned into an Active Channel Web site when you create a CDF file for the site by using any text editor. The author of the site can optimize and personalize the site and control how it is webcast to users. This is essentially a form of “smart pull” technology.
“True” webcasting: Uses Internet Protocol (IP) multicasting to push content to the browsers of users who belong to a multicast group. This is an example of true push technology.
NOTE
The term “webcasting” is sometimes used to refer to the broadcasting of radio programs over the Internet.
See also Channel Definition Format (CDF)
Hosting of Web content for other businesses. Web hosting providers range from local Internet service providers (ISPs) who provide businesses with a few dozen megabytes of server space and access to Perl scripting engines to global-presence companies with server farms that offer dedicated servers, e-mail accounts, domain name holding, support for Web content development tools such as Microsoft FrontPage, support for Web application development platforms such as Microsoft Visual InterDev, open database connectivity (ODBC) support, domain name hosting and holding services, and so on. Some industry watchers estimate that about two-thirds of all corporate Web sites are hosted by Web hosting service providers.
NOTE
Web hosting became big business around 1998. Web hosting providers are rapidly being supplanted by “content hosting” providers that offer an even greater range of services, which can include back-end system integration, custom programming, security management, and site mirroring. However, the distinction between the terms “Web hosting” and “content hosting” is often blurred in this rapidly evolving market.
TIP
When you shop for a Web hosting or content hosting service provider, find out what degree of availability they guarantee. Some providers offer 100 percent availability with no downtime and give clients a refund if any downtime occurs, even a few minutes. They can ensure 100 percent availability by hosting sites on multiple redundant servers and scheduling maintenance so that one server is always online.
Also be sure that the provider offers the full range of services that you require (or might soon require), such as database access and site mirroring. Find out the size of the pipe connecting the provider with the Internet backbone and at which point of presence (POP) the provider is connected to the Internet. For business hosting purposes, a minimum dual OC3 connection with guaranteed 155-Mbps throughput is recommended. Decide whether you want dedicated or shared hosting—that is, whether you are willing to share a server and its network bandwidth with other companies or whether you require the stability, reliability, and throughput of your own dedicated Web server.
A graphic display generated by Content Analyzer (a tool included with Microsoft Site Server and Microsoft Site Server Express) that allows Web server administrators to view the structure and integrity of their Web sites. Web maps can display all or selected portions of a site, including Hypertext Markup Language (HTML) files, graphics files, Java applets, and any other type of object. Administrators can use the Web map to determine the properties of any object in the site, such as the date when the object was last modified or its file size.
Web maps can be displayed in two different views:
Tree view: Displays a hierarchical picture of the objects in the site. This view is similar to the left pane of Windows Explorer.
Hyperbolic view: Displays the objects in the site in a dynamic nonlinear form that you can drag and manipulate to change its size and shape.
A file of text information formatted using Hypertext Markup Language (HTML), and possibly including scripts and active content, that is sent by a Web server in response to a Web browser’s request. Web pages are generally of two types:
Static Web pages: Stored as files on the server in the same form that they are delivered to the client. These files usually have the extension .htm or .html.
Dynamic Web pages: Pages with included scripts, ActiveX components, Java applets, ActiveX Data Objects (ADO), open database connectivity (ODBC) technologies, Dynamic HTML, or any other type of active content. They can also be Web pages that don’t actually exist on the server until the client requests them, whereupon they are generated by the server using Active Server Pages (ASP) or some other server-side technology.
See also Hypertext Markup Language (HTML), Web browser
An application that supports the server side of the Hypertext Transfer Protocol (HTTP), the Internet protocol for the World Wide Web (WWW). Web servers are used to publish content on corporate intranets and over the Internet. To access content on a Web server, you use a Web browser, which supports the client side of HTTP.
Web servers were originally developed on the UNIX platform and were designed for publishing static Web content consisting of ASCII text files formatted using Hypertext Markup Language (HTML). Dynamic content such as forms and search engines were soon added using the Common Gateway Interface (CGI) in scripts written in interpretive languages such as Perl. On Microsoft operating system platforms, Active Server Pages (ASP) and the Internet Server API (ISAPI) are two technologies that you can use to develop dynamic Web content.
An example of a Web server is Internet Information Server (IIS), Microsoft’s Web server for Windows NT Server 4.0. (In Windows 2000 Server, this component is called Internet Information Services.) IIS is a powerful Web application development platform that is managed through a graphical user interface called the Microsoft Management Console (MMC). In addition to supporting HTTP, IIS supports File Transfer Protocol (FTP), Simple Mail Transfer Protocol (SMTP), and Network News Transfer Protocol (NNTP), as well as the Secure Sockets Layer (SSL) and Secure/Multipurpose Internet Mail Extensions (S/MIME) security protocols. IIS also supports Microsoft FrontPage, which is a Web site development tool.
Another popular Web server is Apache, an open source application for UNIX platforms (which has been ported to other platforms as well). Apache was originally based on the National Center for Supercomputing Applications’ httpd Web server daemon, which is no longer being developed. Apache is popular with Internet service providers (ISPs) that were founded within the university environment from which the Internet originated.
Other popular Web servers include Netscape Enterprise Server and Netscape FastTrack Server from Netscape Communications and Lotus Domino, the Web server component of Lotus Notes.
On the Web
•
Apache home page : http://www.apache.org
•
Windows NT Web services : http://www.microsoft.com/ntserver/web/
See also Hypertext Transfer Protocol (HTTP), Web browser
Port numbers for Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) that have been assigned to specific TCP/IP applications or services by the Internet Assigned Numbers Authority (IANA). Well-known port numbers are assigned within the range 0 through 1023 and are specified in Request for Comments (RFC) 1060. (The total range of possible port numbers is 0 through 65535.) The following table describes some of the well-known port numbers.
NOTE
“Registered ports” are port numbers that are not controlled by IANA but that IANA registers to indicate to the Internet community which vendor applications use them. Registered ports range from 1024 through 65535 and can be used by any process or program requesting it if the operating system has not already allocated it for a specific use. Programs and processes that communicate using remote procedure calls (RPCs) often randomly select a registered port for each RPC communication session.
Well-Known Port Numbers
| Port Number | Keyword | Description |
| 0/tcp, udp | Reserved | |
| 1/tcp, udp | tcpmux | TCP Port Service Multiplexer |
| 2/tcp, udp | compressnet | Management Utility |
| 3/tcp, udp | compressnet | Compression Process |
| 4/tcp, udp | Unassigned | |
| 5/tcp, udp | rje | Remote Job Entry |
| 6/tcp, udp | Unassigned | |
| 7/tcp, udp | echo | Echo |
| 8/tcp, udp | Unassigned | |
| 9/tcp, udp | discard | Discard; alias = sink null |
| 10/tcp, udp | Unassigned | |
| 11/tcp, udp | systat | Active Users; alias = users |
| 12/tcp, udp | Unassigned | |
| 13/tcp, udp | daytime | Daytime |
| 14/tcp, udp | Unassigned | |
| 15/tcp, udp | Unassigned (was netstat) | |
| 16/tcp, udp | Unassigned | |
| 17/tcp, udp | qotd | Quote of the Day; alias = quote |
| 18/tcp, udp | msp | Message Send Protocol |
| 19/tcp, udp | chargen | Character Generator; alias = ttytst source |
| 20/tcp, udp | ftp-data | File Transfer (default data) |
| 21/tcp, udp | ftp | File Transfer (control), connection dialog |
| 22/tcp, udp | Unassigned | |
| 23/tcp, udp | telnet | Telnet |
| 24/tcp, udp | Any private mail system | |
| 25/tcp, udp | smtp | Simple Mail Transfer; alias = mail |
| 26/tcp, udp | Unassigned | |
| 27/tcp, udp | nsw-fe | NSW User System FE |
| 28/tcp, udp | Unassigned | |
| 29/tcp, udp | msg-icp | MSG ICP |
| 30/tcp, udp | Unassigned | |
| 31/tcp, udp | msg-auth | MSG Authentication |
| 32/tcp, udp | Unassigned | |
| 33/tcp, udp | dsp | Display Support Protocol |
| 34/tcp, udp | Unassigned | |
| 35/tcp, udp | Any private printer server | |
| 36/tcp, udp | Unassigned | |
| 37/tcp, udp | time | Time; alias = timeserver |
| 38/tcp, udp | Unassigned | |
| 39/tcp, udp | rlp | Resource Location Protocol; alias = resource |
| 40/tcp, udp | Unassigned | |
| 41/tcp, udp | graphics | Graphics |
| 42/tcp, udp | nameserver | Host Name Server; alias = nameserver |
| 43/tcp, udp | nicname | Who Is; alias = nicname |
| 44/tcp, udp | mpm-flags | MPM FLAGS Protocol |
| 45/tcp, udp | mpm | Message Processing Module |
| 46/tcp, udp | mpm-snd | MPM (default send) |
| 47/tcp, udp | ni-ftp | NI FTP |
| 48/tcp, udp | Unassigned | |
| 49/tcp, udp | login | Login Host Protocol |
| 50/tcp, udp | re-mail-ck | Remote Mail Checking Protocol |
| 51/tcp, udp | la-maint | IMP Logical Address Maintenance |
| 52/tcp, udp | xns-time | XNS Time Protocol |
| 53/tcp, udp | domain | Domain Name Server |
| 54/tcp, udp | xns-ch | XNS Clearinghouse |
| 55/tcp, udp | isi-gl | ISI Graphics Language |
| 56/tcp, udp | xns-auth | XNS Authentication |
| 57/tcp, udp | Any private terminal access | |
| 58/tcp, udp | xns-mail | XNS Mail |
| 59/tcp, udp | Any private file service | |
| 60/tcp, udp | Unassigned | |
| 61/tcp, udp | ni-mail | NI MAIL |
| 62/tcp, udp | acas | ACA Services |
| 63/tcp, udp | via-ftp | VIA Systems – FTP |
| 64/tcp, udp | covia | Communications Integrator (CI) |
| 65/tcp, udp | tacacs-ds | TACACS-Database Service |
| 66/tcp, udp | sql*net | Oracle SQL*NET |
| 67/tcp, udp | bootpc | DHCP/BOOTP Protocol Server |
| 68/tcp, udp | bootpc | DHCP/BOOTP Protocol Server |
| 69/tcp, udp | tftp | Trivial File Transfer |
| 70/tcp, udp | gopher | Gopher |
| 71/tcp, udp | netrjs-1 | Remote Job Service |
| 72/tcp, udp | netrjs-2 | Remote Job Service |
| 73/tcp, udp | netrjs-3 | Remote Job Service |
| 74/tcp, udp | netrjs-4 | Remote Job Service |
| 75/udp | Any private dial-out service | |
| 76/tcp, udp | Unassigned | |
| 77/tcp, udp | Any private RJE service | |
| 78/tcp, udp | vettcp | Vettcp |
| 79/tcp, udp | finger | Finger |
| 80/tcp, udp | www | World Wide Web HTTP |
| 81/tcp, udp | hosts2-ns | HOSTS2 Name Server |
| 82/tcp, udp | xfer | XFER Utility |
| 83/tcp, udp | mit-ml-dev | MIT ML Device |
| 84/tcp, udp | ctf | Common Trace Facility |
| 85/tcp, udp | mit-ml-dev | MIT ML Device |
| 86/tcp, udp | mfcobol | Micro Focus Cobol |
| 87/tcp, udp | Any private terminal link; alias = ttylink | |
| 88/tcp, udp | kerberos | Kerberos |
| 89/tcp, udp | su-mit-tg | SU/MIT Telnet Gateway |
| 90/tcp, udp | DNSIX Security Attribute Token Map | |
| 91/tcp, udp | mit-dov | MIT Dover Spooler |
| 92/tcp, udp | npp | Network Printing Protocol |
| 93/tcp, udp | dcp | Device Control Protocol |
| 94/tcp, udp | objcall | Tivoli Object Dispatcher |
| 95/tcp, udp | supdup | SUPDUP |
| 96/tcp, udp | dixie | DIXIE Protocol Specification |
| 97/tcp, udp | swift-rvf | Swift Remote Virtual File Protocol |
| 98/tcp, udp | tacnews | TAC News |
| 99/tcp, udp | metagram | Metagram Relay |
| 100/tcp | newacct | (unauthorized use) |
| 101/tcp, udp | hostname | NIC Host Name Server; alias = hostname |
| 102/tcp, udp | iso-tsap | ISO-TSAP |
| 103/tcp, udp | gppitnp | Genesis Point-to-Point Trans Net; alias = webster |
| 104/tcp, udp | acr-nema | ACR-NEMA Digital Imag. & Comm. 300 |
| 105/tcp, udp | csnet-ns | Mailbox Name Nameserver |
| 106/tcp, udp | 3com-tsmux | 3COM-TSMUX |
| 107/tcp, udp | rtelnet | Remote Telnet Service |
| 108/tcp, udp | snagas | SNA Gateway Access Server |
| 109/tcp, udp | pop2 | Post Office Protocol version 2 (POP2); alias = postoffice |
| 110/tcp, udp | pop3 | Post Office Protocol version 3 (POP3); alias = postoffice |
| 111/tcp, udp | sunrpc | SUN Remote Procedure Call |
| 112/tcp, udp | mcidas | McIDAS Data Transmission Protocol |
| 113/tcp, udp | auth | Authentication Service; alias = authentication |
| 114/tcp, udp | audionews | Audio News Multicast |
| 115/tcp, udp | sftp | Simple File Transfer Protocol |
| 116/tcp, udp | ansanotify | ANSA REX Notify |
| 117/tcp, udp | uucp-path | UUCP Path Service |
| 118/tcp, udp | sqlserv | SQL Services |
| 119/tcp, udp | nntp | Network News Transfer Protocol (NNTP); alias = usenet |
| 120/tcp, udp | cfdptkt | CFDPTKT |
| 121/tcp, udp | erpc | Encore Expedited Remote Pro. Call |
| 122/tcp, udp | smakynet | SMAKYNET |
| 123/tcp, udp | ntp | Network Time Protocol; alias = ntpd ntp |
| 124/tcp, udp | ansatrader | ANSA REX Trader |
| 125/tcp, udp | locus-map | Locus PC-Interface Net Map Server |
| 126/tcp, udp | unitary | Unisys Unitary Login |
| 127/tcp, udp | locus-con | Locus PC-Interface Conn Server |
| 128/tcp, udp | gss-xlicen | GSS X License Verification |
| 129/tcp, udp | pwdgen | Password Generator Protocol |
| 130/tcp, udp | cisco-fna | Cisco FNATIVE |
| 131/tcp, udp | cisco-tna | Cisco TNATIVE |
| 132/tcp, udp | cisco-sys | Cisco SYSMAINT |
| 133/tcp, udp | statsrv | Statistics Service |
| 134/tcp, udp | ingres-net | INGRES-NET Service |
| 135/tcp, udp | loc-srv | Location Service |
| 136/tcp, udp | profile | PROFILE Naming System |
| 137/tcp, udp | netbios-ns | NetBIOS Name Service |
| 138/tcp, udp | netbios-dgm | NetBIOS Datagram Service |
| 139/tcp, udp | netbios-ssn | NetBIOS Session Service |
| 140/tcp, udp | emfis-data | EMFIS Data Service |
| 141/tcp, udp | emfis-cntl | EMFIS Control Service |
| 142/tcp, udp | bl-idm | Britton-Lee IDM |
| 143/tcp, udp | imap2 | Interim Mail Access Protocol v2 |
| 144/tcp, udp | news | NewS; alias = news |
| 145/tcp, udp | uaac | UAAC Protocol |
| 146/tcp, udp | iso-ip0 | ISO-IP0 |
| 147/tcp, udp | iso-ip | ISO-IP |
| 148/tcp, udp | cronus | CRONUS-SUPPORT |
| 149/tcp, udp | aed-512 | AED 512 Emulation Service |
| 150/tcp, udp | sql-net | SQL-NET |
| 151/tcp, udp | hems | HEMS |
| 152/tcp, udp | bftp | Background File Transfer Program |
| 153/tcp, udp | sgmp | SGMP; alias = sgmp |
| 154/tcp, udp | netsc-prod | Netscape |
| 155/tcp, udp | netsc-dev | Netscape |
| 156/tcp, udp | sqlsrv | SQL Service |
| 157/tcp, udp | knet-cmp | KNET/VM Command/Message Protocol |
| 158/tcp, udp | pcmail-srv | PCMail Server; alias = repository |
| 159/tcp, udp | nss-routing | NSS-Routing |
| 160/tcp, udp | sgmp-traps | SGMP-TRAPS |
| 161/tcp, udp | snmp | SNMP; alias = snmp |
| 162/tcp, udp | snmptrap | SNMPTRAP |
| 163/tcp, udp | cmip-man | CMIP/TCP Manager |
| 164/tcp, udp | cmip-agent | CMIP/TCP Agent |
| 165/tcp, udp | xns-courier | Xerox |
| 166/tcp, udp | s-net | Sirius Systems |
| 167/tcp, udp | namp | NAMP |
| 168/tcp, udp | rsvd | RSVD |
| 169/tcp, udp | send | SEND |
| 170/tcp, udp | print-srv | Network PostScript |
| 171/tcp, udp | multiplex | Network Innovations Multiplex |
| 172/tcp, udp | cl/1 | Network Innovations CL/1 |
| 173/tcp, udp | xyplex-mux | Xyplex |
| 174/tcp, udp | mailq | MAILQ |
| 175/tcp, udp | vmnet | VMNET |
| 176/tcp, udp | genrad-mux | GENRAD-MUX |
| 177/tcp, udp | xdmcp | X Display Manager Control Protocol |
| 178/tcp, udp | nextstep | NextStep Window Server |
| 179/tcp, udp | bgp | Border Gateway Protocol (BGP) |
| 180/tcp, udp | ris | Intergraph |
| 181/tcp, udp | unify | Unify |
| 182/tcp, udp | audit | Unisys Audit SITP |
| 183/tcp, udp | ocbinder | OCBinder |
| 184/tcp, udp | ocserver | OCServer |
| 185/tcp, udp | remote-kis | Remote-KIS |
| 186/tcp, udp | kis | KIS Protocol |
| 187/tcp, udp | aci | Application Communication Interface |
| 188/tcp, udp | mumps | Plus Five’s MUMPS |
| 189/tcp, udp | qft | Queued File Transport |
| 190/tcp, udp | gacp | Gateway Access Control Protocol |
| 191/tcp, udp | prospero | Prospero |
| 192/tcp, udp | osu-nms | OSU Network Monitoring System |
| 193/tcp, udp | srmp | Spider Remote Monitoring Protocol |
| 194/tcp, udp | irc | Internet Relay Chat (IRC) Protocol |
| 195/tcp, udp | dn6-nlm-aud | DNSIX Network Level Module Audit |
| 196/tcp, udp | dn6-smm-red | DNSIX Session Mgt Module Audit Redir |
| 197/tcp, udp | dls | Directory Location Service |
| 198/tcp, udp | dls-mon | Directory Location Service Monitor |
| 199/tcp, udp | smux | SMUX |
| 200/tcp, udp | src | IBM System Resource Controller |
| 201/tcp, udp | at-rtmp | AppleTalk Routing Maintenance |
| 202/tcp, udp | at-nbp | AppleTalk Name Binding |
| 203/tcp, udp | at-3 | AppleTalk Unused |
| 204/tcp, udp | at-echo | AppleTalk Echo |
| 205/tcp, udp | at-5 | AppleTalk Unused |
| 206/tcp, udp | at-zis | AppleTalk Zone Information |
| 207/tcp, udp | at-7 | AppleTalk Unused |
| 208/tcp, udp | at-8 | AppleTalk Unused |
| 209/tcp, udp | tam | Trivial Authenticated Mail Protocol |
| 210/tcp, udp | z39.50 | ANSI Z39.50 |
| 211/tcp, udp | 914c/g | Texas Instruments 914C/G Terminal |
| 212/tcp, udp | anet | ATEXSSTR |
| 213/tcp, udp | ipx | Internetwork Packet Exchange (IPX) |
| 214/tcp, udp | vmpwscs | VM PWSCS |
| 215/tcp, udp | softpc | Insignia Solutions |
| 216/tcp, udp | atls | Access Technology License Server |
| 217/tcp, udp | dbase | dBASE UNIX |
| 218/tcp, udp | mpp | Netix Message Posting Protocol |
| 219/tcp, udp | uarps | Unisys ARPs |
| 220/tcp, udp | imap3 | Interactive Mail Access Protocol v3 |
| 221/tcp, udp | fln-spx | Berkeley rlogind with SPX auth |
| 222/tcp, udp | fsh-spx | Berkeley rshd with SPX auth |
| 223/tcp, udp | cdc | Certificate Distribution Center |
| 224–241 | Reserved | |
| 243/tcp, udp | sur-meas | Survey Measurement |
| 245/tcp, udp | link | LINK |
| 246/tcp, udp | dsp3270 | Display Systems Protocol |
| 247–255 | Reserved | |
| 345/tcp, udp | pawserv | Perf Analysis Workbench |
| 346/tcp, udp | zserv | Zebra server |
| 347/tcp, udp | fatserv | Fatmen Server |
| 371/tcp, udp | clearcase | Clearcase |
| 372/tcp, udp | ulistserv | UNIX Listserv |
| 373/tcp, udp | legent-1 | Legent Corporation |
| 374/tcp, udp | legent-2 | Legent Corporation |
| 512/tcp | | Microsoft Windows NT Server and Windows NT Workstation 4 can send LPD client print jobs from any available reserved port between 512 and 1023; see also the description for ports 721 to 731 |
| 512/udp | biff | Used by the mail system to notify users of new mail received; currently receives messages only from processes on the same computer; alias = comsat |
| 513/tcp | login | Remote logon such as Telnet; automatic authentication performed based on privileged port numbers and distributed databases that identify “authentication domains” |
| 513/udp | who | Maintains databases showing who’s logged on to the computers on a local net and the load average of the computer; alias = whod |
| 514/tcp | cmd | Like exec, but automatic authentication is performed as for logon server |
| 514/udp | syslog | |
| 515/tcp, udp | printer | Spooler; the print server LPD service listens on tcp port 515 for incoming connections; alias = spooler |
| 517/tcp, udp | talk | Like tenex link, but across computers; unfortunately, doesn’t use link protocol (actually just a rendezvous port from which a TCP connection is established) |
| 518/tcp, udp | ntalk | |
| 519/tcp, udp | utime | Unixtime |
| 520/tcp | efs | Extended filename server |
| 520/udp | router | Local routing process (on site); uses variant of Xerox NS routing information protocol; alias = router routed |
| 525/tcp, udp | timed | Timeserver |
| 526/tcp, udp | tempo | Newdate |
| 530/tcp, udp | courier | RPC |
| 531/tcp | conference | Chat |
| 531/udp | rvd-control | MIT disk |
| 532/tcp, udp | netnews | Readnews |
| 533/tcp, udp | netwall | For emergency broadcasts |
| 540/tcp, udp | uucp | Uucpd |
| 543/tcp, udp | klogin | |
| 544/tcp, udp | kshell | Krcmd; alias = cmd |
| 550/tcp, udp | new-rwho | New-who |
| 555/tcp, udp | dsf | |
| 556/tcp, udp | remotefs | Rfs server; alias = rfs_server rfs |
| 560/tcp, udp | rmonitor | Rmonitord |
| 561/tcp, udp | monitor | |
| 562/tcp, udp | chshell | Chcmd |
| 564/tcp, udp | 9pfs | Plan 9 file service |
| 565/tcp, udp | whoami | Whoami |
| 570/tcp, udp | meter | Demon |
| 571/tcp, udp | meter | Udemon |
| 600/tcp, udp | ipcserver | Sun IPC server |
| 607/tcp, udp | nqs | Nqs |
| 666/tcp, udp | doom | Reserved for Id software |
| 704/tcp, udp | elcsd | Errlog copy/server daemon |
| 721–731/tcp | printer | In Windows NT 3.5, all TCP/IP print jobs sent from a computer running Windows NT were sourced from TCP ports 721 through 731; Windows NT 4 and Windows 2000 source LPD client print jobs from any available reserved port between 512 and 1023 |
| 740/tcp, udp | netcp | NETscout Control Protocol |
| 741/tcp, udp | netgw | NetGW |
| 742/tcp, udp | netrcs | Network-based Rev. Cont. Sys. |
| 744/tcp, udp | flexlm | Flexible License Manager |
| 747/tcp, udp | fujitsu-dev | Fujitsu Device Control |
| 748/tcp, udp | ris-cm | Russell Info Sci Calendar Manager |
| 749/tcp, udp | kerberos-adm | Kerberos administration |
| 750/tcp | rfile | Kerberos authentication; alias = kdc |
| 750/udp | loadav | |
| 751/tcp, udp | pump | Kerberos authentication |
| 752/tcp, udp | qrh | Kerberos password server |
| 753/tcp, udp | rrh | Kerberos userreg server |
| 754/tcp, udp | tell | Send; Kerberos slave propagation |
| 758/tcp, udp | nlogin | |
| 759/tcp, udp | con | |
| 760/tcp, udp | ns | |
| 761/tcp, udp | rxe | |
| 762/tcp, udp | quotad | |
| 763/tcp, udp | cycleserv | |
| 764/tcp, udp | omserv | |
| 765/tcp, udp | webster | |
| 767/tcp, udp | phonebook | Phone |
| 769/tcp, udp | vid | |
| 770/tcp, udp | cadlock | |
| 771/tcp, udp | rtip | |
| 772/tcp, udp | cycleserv2 | |
| 773/tcp | submit | |
| 773/udp | notify | |
| 774/tcp | rpasswd | |
| 774/udp | acmaint_dbd | |
| 775/tcp | entomb | |
| 775/udp | acmaint_transd | |
| 776/tcp, udp | wpages | |
| 780/tcp, udp | wpgs | |
| 781/tcp, udp | hp-collector | HP performance data collector |
| 782/tcp, udp | hp-managed-node | HP performance data managed node |
| 783/tcp, udp | hp-alarm-mgr | HP performance data alarm manager |
| 800/tcp, udp | mdbs_daemon | |
| 801/tcp, udp | device | |
| 888/tcp | erlogin | Logon and environment passing |
| 996/tcp, udp | xtreelic | XTREE License Server |
| 997/tcp, udp | maitrd | |
| 998/tcp | busboy | |
| 998/udp | puparp | |
| 999/tcp | garcon | |
| 999/udp | applix | Applix ac |
| 999/tcp, udp | puprouter | |
| 1000/tcp | cadlock | |
| 1000/udp | ock |
A geographically distributed network composed of local area networks (LANs) joined into a single large network using services provided by common carriers. Wide area networks (WANS) are commonly implemented in enterprise networking environments in which company offices are in different cities, states, or countries or on different continents.
WAN technologies were previously limited to expensive leased lines such as T1 lines, slow packet-switching services such as X.25, cheap but low-bandwidth solutions such as modems, and dial-up Integrated Services Digital Network (ISDN) connections, but this has changed considerably in recent years. Frame relay services provide high-speed packet-switching services that offer more bandwidth than X.25, and virtual private networks (VPNs) created using Internet Protocol (IP) tunneling technologies enable companies to securely connect branch offices by using the Internet as a backbone service. Intranets and extranets provide remote and mobile users with access to company resources and applications and provide connectivity with business partners and resellers. Wireless networking technologies allow roaming users to access network resources by using cell-based technologies. Digital Subscriber Line (DSL) services provide T1 speeds at much lower costs than dedicated T1 circuits. These and other new technologies continue to evolve and proliferate, allowing enterprise network administrators to implement and administer a highly diverse range of WAN solutions.
See also frame relay, Integrated Services Digital Network (ISDN), leased line, WAN link, X.25
A wireless communication technology derived from Code Division Multiple Access (CDMA) cellular phone technology that is proposed for 3G (third-generation) wireless communication systems. Wideband Code Division Multiple Access (W-CDMA) uses wider frequency bands than CDMA, so it can achieve higher throughput for data transmission. The Universal Mobile Telecommunications System (UMTS) standard proposed by the European Telecommunications Standards Institute (ETSI) and incorporated into the International Mobile Telecommunications-2000 (IMT-2000) initiative of the International Telecommunication Union (ITU) is partly based on W-CDMA.
W-CDMA is not fully compatible with air and network interfaces of the proposed CDMA2000 standard, which is another part of the IMT-2000 initiative, and it is not compatible with the air interface of the existing Global System for Mobile Communications (GSM) cellular phone network. The CDMA2000 standard uses synchronous base station transmissions with 20-millisecond frames, while W-CDMA uses asynchronous base station transmissions with 10-millisecond frames.
See Microsoft Windows
The GUI-based operating system from Microsoft that made personal computers easier and more fun to use. Microsoft Windows went through several earlier versions, but the first widely used version was Windows 3.0, which was released in 1990 and provided users with a graphical user interface (GUI) environment that was easier to learn and use than the command-line environment of the MS-DOS operating system. In 1992, Microsoft released Windows 3.1, which included additional enhancements and utilities. Windows 3.1 is now considered a legacy operating system and has largely been replaced by Windows 95, Windows 98, Windows NT, and Windows 2000 in homes and businesses.
Unique features of Windows 3.1 that distinguished it from earlier operating systems such as MS-DOS include the following:
A GUI that displays applications in separate windows that can be resized and arranged in any fashion
Virtual memory, a technique for swapping between RAM and disk space that increases the number of applications that can be run simultaneously
Customizable user interface elements, including the color scheme, fonts, arrangement of windows, and mouse settings
Data sharing by applications using Dynamic Data Exchange (DDE) and object linking and embedding (OLE)
TrueType fonts, which are displayed in WYSIWYG fashion and can be scaled to any size
Device independence, which makes it easier for manufacturers to write device drivers for their hardware
Network-aware File Manager and Print Manager utilities, which enable access to shared network drives and printers
Graphic W-2. Windows 3.1 User interface.
How It Works
Windows 3.1 is a 16-bit cooperative multitasking graphical operating system that runs on top of MS-DOS and shares some architectural similarities with MS-DOS. Windows 3.1 uses a layered architecture (see the following figure) consisting of three main components:
A top-layer Windows application programming interface (API) that allows software developers to write 16-bit Windows programs without needing to understand the details of how the operating system routines work internally or how device drivers are implemented and communicate with underlying hardware.
A middle layer consisting of Windows core components and extensions. The core components make up the kernel of the operating system and consist of three subcomponents:
Krnl386.exe: Handles basic operating systems such as memory management, process and thread scheduling, and file input/output (I/O)
User.exe: Manages user I/O devices such as the keyboard and mouse, manages communication ports, and keeps track of Windows user interface elements such as windows, dialog boxes, icons, and menus
Gdi.exe: Manages drawing screen graphics and printing
The middle layer also includes extensions to the core operating system components that are supplied in the form of dynamic-link libraries (DLLs) that add extra functionality to the Windows environment, such as multimedia support and DDE. Windows DLLs make the Windows operating system environment extensible, allowing software manufacturers to add basic functionality to Windows by creating their own custom DLLs. Windows optimizes memory usage by dynamically loading only the DLLs that it needs at a given time.
Graphic W-3. Windows 3.1. Architecture.
A bottom layer, consisting of Windows drivers, that provides device drivers for different hardware devices managed by Windows, such as the keyboard, mouse, video display, and communication ports.
Windows 3.1 has two modes of operation:
Standard Mode: Does not use virtual memory and cannot multitask with MS-DOS applications. In Standard Mode, MS-DOS applications can run only full-screen.
386 Enhanced Mode: (See the following diagram.) Requires an Intel 386 or higher processor, uses virtual memory, and supports multitasking of MS-DOS applications in separate windows. This mode includes the Virtual Machine Manager (VMM), which creates and manages separate virtual machines (VMs) running on a single CPU. Each VM functions as though it has access to and control over the resources of the entire system. Windows 3.1 and all 16-bit Windows applications run in a single system VM, while each additional MS-DOS application runs in its own separate DOS VM. Virtual device drivers (VxDs) are 32-bit protected-mode DLLs that allow more than one process to share a system resource simultaneously in order to support multitasking. Windows applications are multitasked cooperatively—that is, they must be written to properly relinquish control to other applications to allow them to share system resources. Running win.com at the MS-DOS prompt invokes the 386 Enhanced Mode system loader (win386.exe).
Windows 3.1 stores its system and operating system configuration information in a series of text files accessed during the boot process. These include the following:
Config.sys and autoexec.bat, which have the same function as in MS-DOS
Win.ini, which configures the Windows desktop and working environment
System.ini, which stores the Windows system configuration, including device drivers and mode settings
Other INI files such as progman.ini, protocol.ini, control.ini, and lanman.ini
Graphic W-4. Windows 3.1. Virtual memory in 386 Enhanced Mode.
NOTE
Windows 3.1 includes a 32-bit file system technology called FastDisk, which filters Int 13H calls to the hard disk controller and uses 32-bit protected-mode device drivers or accesses the disk through the system BIOS, depending on how it is configured. However, this feature is disabled by default when Windows 3.1 is installed; you can turn it on by using the 386 Enhanced utility in Control Panel.
See Windows for Workgroups 3.11
See Windows 3.1, Windows for Workgroups 3.11
Microsoft’s popular 32-bit desktop operating system, which replaced the Windows 3.1 operating system. Windows 95 was designed as a desktop operating system for home, office, and business use that preserves full backward compatibility with applications for legacy 16-bit operating systems such as MS-DOS, Windows 3.1, and Windows for Workgroups.
Graphic W-5. Desktop.
Windows 95 includes the following features:
A redesigned graphical user interface (GUI) with such features as a configurable desktop, taskbar, Start button, and context menus
Compatibility with legacy hardware and with MS-DOS and 16-bit Windows applications
32-bit virtual device drivers (VxDs) for protected-mode management of devices and services
Preemptive multitasking kernel that multitasks Win32 and MS-DOS-based applications, replacing the cooperative multitasking approach used by Windows 3.1
Fully integrated 32-bit disk, network, and print subsystems
Integrated built-in networking software for Microsoft Networks, Novell NetWare, and Banyan Vines
Support for long filenames
Support for plug and play automatic hardware installation and configuration
Advanced Power Management (APM) support for mobile users
Integrated Windows Messaging for e-mail
Integrated dial-up networking for Internet connectivity and for Remote Access Service (RAS) connectivity
Integrated support for multimedia sound and video applications
Microsoft Internet Explorer, an integrated Web browser
Support for advanced features for network administrators, including hardware profiles, user profiles, and system policies
How It Works
The Windows 95 architecture evolved from Windows 3.1 and Windows for Workgroups, but in contrast to these 16-bit versions of Windows, which ran on top of MS-DOS, Windows 95 is a 32-bit operating system with a 32-bit kernel, VxDs, and an Installable File System (IFS) manager and does not require that MS-DOS be loaded on the computer. However, Windows 95 does includes some 16-bit code and 16-bit components to ensure backward compatibility with MS-DOS, Windows 3.1, and Windows for Workgroups. Windows 95 also supports multithreaded operation and preemptive multitasking operation and manages system resources more effectively than earlier versions of Windows, allowing more and larger applications to be multitasked.
Graphic W-6. Architecture.
For added protection against application crashes, Windows 95 supports virtual machines (VMs). VMs in Windows 95 are similar to those implemented in Windows 3.1 except for two differences: in Windows 95, 32-bit Windows applications (Win32 apps) can run within their own protected memory address space within the system VM, and 16-bit Windows applications (Win16 apps) also run in the system VM but share their own address space (since they must be cooperatively multitasked). MS-DOS applications run in individual VMs of their own.
Another change in Windows 95 is that system configuration information that was formerly stored in boot files (config.sys and autoexec.bat) and INI files is stored in a database structure called the registry. The registry is the central repository for all hardware and software configuration information. Boot and INI files are still supported for backward compatibility with legacy hardware and software.
NOTE
Windows 95 went through several incremental releases, each with additional features and enhancements. To determine which version of Windows 95 you are using, run the System utility in Control Panel and look at the version number on the General tab. The incremental versions are described in the following table.
Windows 95 Incremental Releases
| Version Number | Release |
| 4.00.950 | Original full retail version and upgrade from Windows 3.1. |
| 4.00.950A | Windows 95 with Service Pack 1, also called OEM Service Release 1 (OSR1). |
| 4.00.950B | OEM Service Release 2 (OSR2) or OEM Service Release 2.1 (OSR2.1). If “USB Supplement to OSR2” shows up as an installed program when you use the Add/Remove Programs utility in Control Panel, you have OSR2.1 installed. |
| 4.00.950C | OEM Service Release 2.5 (OSR2.5). |
NOTE
If your 20-digit product ID number has “OEM” in it, you have an original equipment manufacturer (OEM) version of Windows 95 that was probably preinstalled on your computer.
See also Windows 3.1
Microsoft’s upgrade for users of Windows 95 and earlier versions of Microsoft Windows operating systems. Windows 98 includes the following new features:
A Web-aware user interface that allows Web-like views of local resources and a single tool for browsing local, network, and Internet resources
Integrated Internet software including Microsoft Internet Explorer, Outlook Express, NetMeeting, Personal Web Server, FrontPad, and NetShow
Windows Update Manager for accessing the Internet to download enhancements and fixes to Windows 98
Improved networking support with a faster TCP/IP protocol stack, improved dial-up networking, and support for virtual private networking
Support for FAT32 drives and a FAT32 conversion utility
Maintenance Wizard for scheduling system maintenance utilities and other new utilities that simplify administration of computers running Windows 98, including the Microsoft System Information utility, System File Checker, Registry Checker, and Windows Scripting Host (for running administrative scripts from the desktop)
Support for digital versatile disc (DVD) and for multiple monitors on a single computer
Support for universal serial bus (USB), FireWire (IEEE 1394), and infrared wireless connectivity based on Infrared Data Association (IrDA) standards
Support for DirectX 5.0 and OnNow instant-on technology
Built-in Remote Access Service (RAS) for remote dial-up clients
HTML-based online help
Improved versions of many Windows 95 tools and utilities
NOTE
The Windows 98 system architecture and user interface are essentially the same as those of Windows 95 with Internet Explorer version 4.0 or later installed using the Active Desktop option.
TIP
When you plan an upgrade for your current desktop operating system, choose Windows 2000 over Windows 98 if you need such features as
Local desktop file security using the NTFS file system
Greater stability and protection for running applications
Scalability and portability to multiprocessor and RISC-based machines
C2 level security
On the other hand, you should choose Windows 98 over Windows 2000 if you need any of the following:
Full backward compatibility with MS-DOS and 16-bit Windows applications
Support for legacy hardware and lower overall hardware requirements
Advanced Power Management (APM) for mobile users
Support for games
See also Windows 95
The latest version of the Microsoft Windows operating system, which was designed as the successor to Windows NT and, to some extent, Windows 98. The Windows 2000 family has four members:
Windows 2000 Professional: A desktop operating system that replaces Windows NT Workstation 4 and builds on the ease-of-use of Windows 98 and the power and reliability of Windows NT. Windows 2000 Professional includes the following features:
Wizards for simplifying system configuration and common system maintenance tasks, and time-saving improvements for the user interface, including Microsoft Internet Explorer 5, an integrated Web browser
Features for mobile users, including Advanced Configuration and Power Interface (ACPI) support for laptop power management and offline files, and Synchronization Manager for remote use of network resources
Support for 4-GB RAM, two-way symmetric multiprocessing (SMP), universal serial bus (USB) and IEEE 1394 interfaces, Microsoft DirectX 7, OpenGL 1.2, video port extensions, and digital versatile disc (DVD) and smart card technologies
IntelliMirror client for deployment and maintenance in conjunction with Windows 2000 Server
Local data protection using the Encrypting File System (EFS)
Support for TCP/IP virtual private networking using Point-to-Point Tunneling Protocol (PPTP), Layer 2 Tunneling Protocol (L2TP), and Internet Protocol Security (IPSec)
Add-on Windows Services for UNIX components for interoperability with UNIX networking environments, including a Network File System (NFS) client and server, Telnet client and server, scripting tools, and password synchronization features
Windows 2000 Server, Standard Edition: A comprehensive application, file, print, and Internet services platform that replaces Windows NT Server 4 and provides increased reliability, scalability, management, and applications support. Its features include the following:
Active Directory, a directory service based on the X.500 directory specifications that simplifies centralized, one-point management of distributed network resources.
Windows Management Tools, which are snap-ins for the Microsoft Management Console (MMC). MMC provides a unified interface for managing enterprise-level network resources.
Enhanced Internet services, including Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), Simple Mail Transfer Protocol (SMTP), and Network News Transfer Protocol (NNTP) server support through Internet Information Services (IIS).
Windows Terminal Services for running terminal emulation on thin clients, replacing Windows NT Server, Terminal Server Edition.
Four-way SMP support.
Enhanced COM+ component services.
Support for Kerberos and public key infrastructure (PKI) security services.
Windows 2000 Advanced Server: A powerful server operating system that replaces Windows NT Server 4, Enterprise Edition, Windows 2000 Advanced Server is designed for enterprise-level networking environments that require high availability and scalability. Its features include all those in Windows 2000 Server, Standard Edition, plus the following:
Support for up to 64-GB RAM (through Intel’s Physical Address Extensions) and eight-way SMP
Network-based and component-based load balancing with failover clustering
High-performance sorting
Windows 2000 Datacenter Server: Designed to be the high end of the Windows 2000 Server family when it is released. It will support all features of Windows 2000 Advanced Server plus advanced clustering and 16-way SMP, with 32-way SMP available through original equipment manufacturers (OEMs)
Graphic W-7. Desktop.
NOTE
The architecture of Windows 2000 is similar to that of Windows NT. Some of the notable differences include the following:
The kernel is modified to include support for Terminal Services.
Kernel Mode includes two new modules: Plug and Play Manager and Power Manager.
I/O Manager includes additional drivers for Asynchronous Transfer Mode (ATM), quality of service (QoS), and so on.
TIP
If you are a Windows NT system administrator who is moving to the more powerful and scalable Windows 2000 operating system platform, you might be confused at first by the differences between administrative tools on the two platforms. The following table is designed to help you get up to speed quickly on Windows 2000 system administration by highlighting some of the differences between the basic administrative tools on the Windows NT and Windows 2000 platforms. Note that there is usually no one-to-one correspondence between tools on the two platforms; what can be done with one tool on Windows NT might require several on Windows 2000, and vice versa. The tools listed in the second column are therefore not exact equivalents of those in the first column. Unless otherwise indicated, all Windows 2000 tools referred to are in the Administrative Tools program group, which can be accessed either from the Start menu or from Control Panel.
Comparison of Administrative Tools in Windows 2000 and Windows NT
| Windows NT Administrative Tool | Windows 2000 Equivalent(s) |
| Administrative Wizards | Configure Your Server (Various consoles also have integrated wizards.) |
| Backup | Backup (in System Tools in Accessories) |
| Disk Administrator | Computer Management |
| Event Viewer | Event Viewer |
| License Manager | Licensing |
| Network Client Administrator | No equivalent |
| Performance Monitor | Performance |
| Remote Access Admin | Routing and Remote Access |
| Server Manager | Computer Management |
| System Policy Editor | Active Directory Users and Computers Group Policy |
| User Manager for Domains | Active Directory Users and Computers Active Directory Domains and Trusts |
| Windows NT Diagnostics | Computer Management |
See also Windows NT
See Windows NT command
A Microsoft Windows 2000 utility for backing up and restoring important data to tape. Windows Backup is accessed through the System Tools group in the Accessories group.
How It Works
With Windows Backup, you can either manually back up volumes or schedule unattended backup jobs to be performed automatically on a regular basis. Windows Backup lets you back up data either to a tape drive or to a file that can be stored on various media including hard disks, removable disks, writable CDs, or optical drives.
Graphic W-8. Windows Backup.
Backup and Restore are initiated and scheduled through a single dialog box (see screen capture). Wizard-based interfaces are used to simplify the backup and restore processes, and they allow you to back up all files on your system, specified files, or only critical system state data essential to the health of the system. You can use the Backup Wizard to perform a normal, copy, incremental, differential, or daily copy backup, and you can choose to either append the backup to the media specified or overwrite the existing backup file on the media. Backups can be run immediately or can be scheduled to run daily, weekly, monthly, at system startup, at logon, or when the system is idle.
In order to back up and restore any files regardless of the permissions they are assigned, users must be members of the Administrators, Backup Operators, or Server Operators group. Ordinary users can back up only their own files and folders, plus any files for which they have read permission. Similarly, ordinary users can restore only their own files and folders, plus any files for which they have write permission.
You must normally close files in order to back them up by using Windows Backup. Operating system files can be backed up even if they are open, however.
NOTE
The corresponding utility on the Microsoft Windows NT platform is called Windows NT Backup. The Windows NT Backup tool supports backup to tape drive only. It does not support volume recovery because it does not back up data at the sector level. The command-line version of this utility is called ntbackup.exe and includes a number of switches that allow you to run it from a batch file that you schedule using the Windows NT at command.
TIP
Prior to running Windows Backup, use the Send Console Message option in the Computer Management console to send an administrative message to all logged-on users instructing them to save their work and close their applications if they want their files to be backed up properly.
TIP
When Microsoft Exchange Server is installed on Windows NT Server, additional functionality is added to the Windows NT Backup tool to simplify backup of critical Exchange directories and files such as the information store.
A Microsoft Windows–compatible real-time operating system for a broad range of products including personal and handheld computers, terminals, and industrial controllers. Windows CE is primarily for embedded systems in which the operating system is hard-coded by a vendor into a device’s ROM and for handheld PCs that provide portable messaging and Internet capability.
How It Works
Windows CE is based on a subset of the standard Win32 API, which means that original equipment manufacturer (OEM) developers can use all of the standard Win32 development tools to create custom-based Windows CE solutions for their Windows CE–based products. Windows CE is a component-based operating system that you can use to create “mix-and-match” operating systems that provide only the functionality needed for an embedded system, thus minimizing the memory requirements of such a system. For example, a Windows CE–based industrial sensor might contain the Windows CE kernel and communication modules but not the graphical user interface (GUI). The available modules include the following:
Operating system kernel (32-bit, multitasking, multithreaded, executes in ROM), graphical device interface (GDI), and USER components
Device drivers (keyboard, touch panel, notification LED, display, audio, battery, PCMCIA, serial devices, and FAT/FAT32 volumes)
Communication components, including support for both wired and wireless local area network (LAN) connectivity, TCP/IP with Windows Sockets, Point-to-Point Protocol (PPP), Serial Line Internet Protocol (SLIP), Infrared Data Association (IrDA) standards, Telephony Application Programming Interface (TAPI), and so on
Windows CE Embedded Shell support, which allows developers to create custom shells for providing a user interface for their CE devices
Win32-like registry for storing configuration information
Windows CE is implemented on a specific hardware platform using a thin layer of code between the kernel and the hardware called the OEM adaptation layer (OAL), which isolates device-specific features of hardware from the operating system kernel, enabling developers to ignore specific hardware functionality.
The current version of Windows CE is 2.1; version 3 will soon be released.
A feature of Microsoft Windows 2000 Advanced Server that uses clustering technologies to provide high availability and scalability for enterprise-level applications. Clustering was first introduced in the Microsoft Windows platform in Windows NT Server 4, Enterprise Edition.
How It Works
A cluster is a collection of multiple independent servers (or nodes) that run a common set of applications but provide clients with the image of a single server. This redundancy enables clustered systems to provide load balancing and failover support, thus greatly increasing reliability and scalability over a single server system. Windows Clustering on Windows 2000 Advanced Server consists of two types of technologies: server clusters and network load balancing clusters.
Server clusters support the failover of resources for applications running on Windows 2000 so that applications and services can continue to function if a server fails or is down for maintenance. Server clusters are implemented through the Cluster service, which you can install using the Windows Components Wizard. If one node of a cluster becomes unavailable, the resources and applications running on the server smoothly migrate to an available node within the cluster with minimum interruption (a process called “failover”). When the failed node is restored, the resources and applications migrate back to the restored node (a process called “failback”). In this context, cluster resources include elements such as IP addresses and shared disk subsystems. Windows 2000 supports active/active clustering, in which every node in a cluster is available to do real work and to handle the resources of failed nodes when needed.
Network load balancing clusters allow up to 32 servers running Windows 2000 Advanced Server to be combined into a single cluster. Network load balancing provides high availability and scalability for TCP/IP-based services and applications by distributing client connections among the servers in a cluster. Each node monitors the status of the cluster by periodically exchanging multicast or broadcast messages with the cluster. If one node of a cluster fails or is taken offline for maintenance, the cluster automatically reconfigures itself and redistributes client connections accordingly to balance the load. This process is called convergence and results in the election of a new default host, which handles all network traffic that is not handled by port rules (filters that administrators can configure to specify the weighting factor for each node for load balancing purposes).
You use the administrative console called Cluster Administrator to manage clusters on Windows 2000. You can create cluster groups, initiate failover, monitor cluster health, and handle maintenance tasks. You can install Cluster Administrator on any computer running Windows 2000, not just those running Advanced Server. You can also use Cluster Administrator from Windows NT Server 4, Enterprise Edition, to manage a Windows 2000 cluster if Windows NT 4 Service Pack 3 or later is installed.
See also clustering, Microsoft Cluster Server (MSCS)
See Microsoft Windows Distributed interNet Applications (DNA) Architecture
The primary tool for accessing file systems in Microsoft Windows NT, Windows 95, Windows 98, and Windows 2000. You can use Windows Explorer (or Windows NT Explorer, as it is called in the Windows NT operating system) to
Create, move, copy, open, edit, and delete files or folders
Search for files using complex queries
Map and disconnect network drives to shared folders on network servers
View and manipulate properties of files and other file system objects
Share folders and printers for use on the network
Configure NTFS permissions, auditing, and ownership (Windows NT and Windows 2000 only)
Windows Explorer displays a hierarchical window-based view of file system and network resources in two panes. The left pane shows a hierarchical view of all available file system resources, including the desktop, local drives, mapped network drives, printers, and Network Neighborhood (in Windows NT, Windows 95, and Windows 98) or My Network Places (in Windows 2000). In Windows 2000, the left pane can also show search tools or a history of recently accessed resources. The right pane shows the files and folders or other objects within the currently selected drive or folder in the left pane.
Graphic W-9. Windows Explorer.
See also My Computer, My Network Places, Network Neighborhood
A version of Microsoft Windows 3.1 released in 1994 that includes integrated networking components. Windows for Workgroups was first released as Windows for Workgroups 3.10; Windows for Workgroups 3.11 added high-performance 32-bit networking access. Windows for Workgroups was released as both a stand-alone product and as an add-on for Windows 3.1.
Windows for Workgroups uses the same graphical user interface (GUI) as Windows 3.1. It includes the following enhancements and features:
Low 4-KB footprint in conventional memory for use with 32-bit network drivers, enabling large MS-DOS applications to be multitasked in a Windows environment
Improved performance with 32-bit networking software that provides support for the network driver interface specification (NDIS) 3 standard, plus backward compatibility with the NDIS 2 standard of the 16-bit Windows 3.1 operating system
Compatibility with Microsoft Windows NT Advanced Server, Novell NetWare, and Banyan Vines
Autodetection of many network interface cards (NICs)
Support for IPX/SPX in addition to the earlier NetBEUI network protocols
Password-protected logon
Integrated mail and fax software
Workgroup version of Microsoft Mail for e-mail connectivity, and the Schedule+ utility for keeping track of appointments and tasks
Additional network utilities such as Chat, Net Watcher, WinPopup, and WinMeter
Graphic W-10. Windows for Workgroups 3.11.
How It Works
The architecture of Windows for Workgroups is essentially the same as that of Windows 3.1 except for the networking subsystem, which supports the newer NDIS 3 standard. Windows for Workgroups also includes enhancements to 32-bit disk access, which is implemented as two Windows virtual device drivers (VxDs): VFAT, a 32-bit, protected-mode replacement for the MS-DOS file allocation table (FAT) file system, and VCACHE, which replaces the MS-DOS SmartDrive disk-caching utility and improves disk input/output (I/O). The network redirector (VREDIR) is implemented as a file system driver as well. The Installable File System (IFS) manager maintains a table that identifies which type of file system device is associated with each disk volume and forwards all I/O calls to the appropriate device.
NOTE
You can add support for advanced TCP/IP features such as Dynamic Host Configuration Protocol (DHCP), Telnet, and File Transfer Protocol (FTP) by using the Microsoft TCP/IP-32 for Windows for Workgroups add-on. You can create the installation disks for this add-on by using Network Client Administrator in Windows NT.
See also Windows 3.1
A Microsoft Windows NT or Windows 2000 service that dynamically registers NetBIOS names of computers on the network. It also provides a central location for resolving these NetBIOS names into IP addresses. Windows Internet Name Service (WINS) is a popular name resolution service on Windows NT networks because it is dynamic, rather than static, making it easier to manage than the Domain Name System (DNS). On the Windows 2000 platform, however, DNS is the main name resolution method now used, while WINS is optionally available as a location service for supporting downlevel (Windows NT, Windows 98, Windows 95, and Windows for Workgroups) servers and clients on the network.
How It Works
In order for NetBIOS hosts (servers and clients running pre–Windows 2000 versions of Microsoft Windows) to communicate on a network, their NetBIOS names must first be resolved into IP addresses. WINS servers, which are servers running Windows NT or Windows 2000 with WINS installed, perform this task. Using WINS servers instead of broadcasts to perform NetBIOS name resolution has several advantages:
Directed traffic to WINS servers generates less network traffic than broadcasts.
WINS provides a mechanism for browsing network resources across multiple domains and subnets.
The WINS database of NetBIOS name to IP address mappings is dynamically maintained, eliminating the need for lmhosts files on clients.
WINS works by requiring each NetBIOS host to register its NetBIOS name to IP address mapping on the WINS server by using a process called name registration. These mappings are temporarily stored in a database called the WINS database and need to be renewed periodically by way of a process called registration renewal. If the IP address of the NetBIOS host changes, the WINS database is automatically updated accordingly. And when a NetBIOS host is shut down, a name release occurs, removing the host’s associated mapping from the WINS database.
If a client computer (typically a computer running Windows NT Workstation, Windows 98, Windows 95, or Windows for Workgroups) wants to connect to a file server running Windows 2000 or Windows NT, it queries a designated WINS server using a name query, providing it with the NetBIOS name of the file server it wants to connect to. The WINS server checks its database and responds to the client with the IP address of the desired file server, enabling the client to locate and connect to the file server.
On the Windows NT Server platform, you manage WINS by using the administrative tool called WINS Manager. This tool can be used for the following tasks:
Maintaining the WINS database of NetBIOS name to IP address mappings
Configuring WINS replication between primary and secondary WINS servers
Creating static mappings for non-WINS computers
On the Windows 2000 Server platform, you manage WINS using the WINS snap-in for the Microsoft Management Console (MMC).
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A single WINS server can support up to about 5000 clients. However, it is a good idea to always use at least two WINS servers in order to provide fault tolerance for NetBIOS name resolution. WINS servers maintain their own separate WINS databases, but they can be configured to replicate their NetBIOS name to IP address mappings by way of a process called WINS database replication.
See also NetBIOS name resolution
Microsoft’s implementation of the Web-Based Enterprise Management (WBEM) architecture for enterprise-level network management. Administrators can use Windows Management Instrumentation (WMI) to track, monitor, and control computers, networking devices, and applications belonging to an enterprise network over the Internet by using a standard Web browser such as Microsoft Internet Explorer. WMI is WBEM-compliant and uses the Common Information Model (CIM) for describing manageable network objects. Support for WMI is built into Microsoft Windows 2000 and Windows 98 and is available as an add-on for Windows NT 4.
How It Works
WMI in Windows 2000 includes two main components:
An object repository that is compliant with the CIM standard and is used for storing information collected from WMI-manageable hardware and software
The CIM Object Manager, which collects information from WMI providers and stores it in the repository
WMI providers function as intermediaries between the network object being managed and WMI. For example, the registry provider allows information to be collected from the registry of remote computers and stored in the repository. Similarly, if Simple Network Management Protocol (SNMP) information needs to be collected from SNMP-manageable devices, the SNMP provider must translate this information into a format suitable for WMI.
Some components of Windows 2000 are WMI-enabled. These are accessible from the Computer Management snap-in, and they include
Logical drives, which you can use to manage local and mapped drives on local or remote computers in order to view drive properties, configure drive security settings, and handle other management tasks
System properties, which you can use to view and modify system properties on local or remote computers, modify virtual memory settings, view and modify computer and domain names, reboot systems, and perform other administrative tasks
System information, which you can collect and display for referencing as you troubleshoot system problems
The Dependencies component of Windows 2000 Services, which you can use to troubleshoot problems arising from service dependencies
You can use a console called the WMI Control to perform general WMI tasks such as enabling error logging, setting permissions for users or groups, and backing up the CIM object repository.
See also Web-Based Enterprise Management (WBEM)
A set of information required by Microsoft Windows messaging applications such as Microsoft Outlook. The Windows Messaging Profile identifies
What information services are used (such as Microsoft Exchange Server or the Internet)
How e-mail is delivered
Where incoming e-mail will be stored
When you install Outlook, a profile is automatically created consisting of the Outlook Address Book and Personal Folders store. You must specify additional information such as the information service to be used before you can use the profile.
NOTE
To facilitate deployment of Outlook in your Exchange organization, you can automatically generate profiles for your Exchange users by using the exchange.prf file from the Microsoft Office 97 Resource Kit and a custom outlook.prf file for each user.
Microsoft’s popular operating system for all types of networks ranging from workgroups to enterprise-level installations. Microsoft Windows NT, which provides a secure, scalable, reliable 32-bit operating system platform, is a component of Microsoft BackOffice and provides the foundation upon which all other BackOffice applications run.
Windows NT was first released in 1993 in two versions—a server version called Windows NT Advanced Server (formerly called LAN Manager for Windows NT) and an associated client version called Windows NT 3.1. In 1994, the product was enhanced and released as Windows NT Server 3.5 and Windows NT Workstation 3.5, which were both soon upgraded to Windows NT 3.51. Windows NT 3.51 includes such networking and security features as
NTFS file system for advanced local and remote file system security
Windows NT domains, which are implemented using domain controllers for secure logons in a networking environment
Trust relationships for building enterprise-level multidomain networks
Centralized storage of user profiles to support roaming users on the network
Remote Access Service (RAS) for supporting remote users
Support for both the server and client sides of Dynamic Host Configuration Protocol (DHCP) and Windows Internet Naming Service (WINS)
Support for the software implementation of RAID levels 0, 1, and 5
Integrated support for the TCP/IP protocol suite and associated utilities
Support for POSIX and OS/2 text-based applications
Services for Apple Macintosh
Support for Novell NetWare migration
In 1996, Windows NT was upgraded to version 4, with new features and enhancements that included the following:
An easy-to-use Microsoft Windows 95–style desktop interface
Administrative wizards
Integrated Internet services and tools, including Internet Information Server (IIS)
Administrative tools such as System Policy Editor, Network Monitor, and Task Manager
Support for both the server and client sides of the Domain Name System (DNS) protocol
Support for the Distributed Component Object Model (DCOM)
Improvements to the core operating system services and components
Graphic W-11. Windows NT 4 user interface.
Windows NT now comes in four forms:
Windows NT Server 4: A fast 32-bit multitasking server operating system for networking environments. It can run as a file and print server, an application server, or an authentication and access control server (domain controller), and it can support as many concurrent connections as licenses purchased and up to 256 concurrent RAS sessions.
Windows NT Workstation 4: A fast 32-bit multitasking desktop operating system that supports up to 10 incoming concurrent sessions and one RAS session.
Windows NT Server 4, Enterprise Edition: Includes Microsoft Cluster Server (MSCS) for two-node clustering, Windows NT Load Balancing Service (WLBS) for load balancing up to 32 servers, eight-way symmetric multiprocessing (and support for up to 32 processors from selected vendors), 4-GB Memory Tuning (4GT), and additional tools and enhancements.
Windows NT Server 4, Terminal Server Edition: Uses terminal emulation to present the familiar 32-bit Windows user interface on Windows-based terminal-embedded devices and on all versions of Windows desktop operating systems, including those running on legacy hardware using the Remote Display Protocol (derived from the T.120 protocol of the International Telecommunication Union).
Graphic W-12. Windows NT 4 architecture.
How It Works
Windows NT components run in one of two modes:
User mode: Contains applications and the various Windows NT subsystems that support them, including the following:
Win32 subsystem: Supports Win32 applications. (All other subsystems are dependent on this subsystem.)
Security subsystem: Responsible for authentication, access control, and implementing security and audit policies.
OS/2 subsystem: Responsible for running text-based OS/2 1.1 applications.
POSIX subsystem: Responsible for running POSIX-compliant UNIX applications.
Windows NT processes that run in user mode are limited to an assigned portion of the system’s overall address space but can use virtual memory as needed. User mode processes run at a lower priority than kernel mode processes and have no direct access to system hardware functions. User mode processes must issue all hardware access requests to the Windows NT executive for fulfillment.
Kernel mode: Processes run at a higher priority than those in user mode and consist of the following:
Windows NT executive services: Implemented in various modules specific to operating system functions. All managers and device drivers are implemented at this level.
Microkernel: Handles core operating system functions such as thread scheduling and interrupt handling.
Hardware abstraction layer (HAL): Makes Windows NT more portable between platforms by isolating hardware-specific differences.
See Windows Backup
An authentication scheme used in Microsoft Windows NT–based networks that enables users to be authenticated without the transmission of actual account information or passwords across the network. Windows NT Challenge/Response Authentication is one of three authentication schemes supported by Internet Information Services (IIS). It is also sometimes known as NTLM, which stands for Windows NT LAN Manager authentication. On the Microsoft Windows 2000 platform, this authentication scheme is now known as Integrated Windows Authentication.
How It Works
When a Web browser such as Microsoft Internet Explorer attempts to connect to an IIS server configured for Windows NT Challenge/Response Authentication, the IIS server challenges the browser to perform a complex mathematical calculation on the password of the logged-on user who is using the browser and to return the result of this calculation to the server. The server also performs the calculation on the user’s password obtained from a domain controller’s Security Account Manager (SAM) database. If the two calculations agree, the client is considered authenticated. If they differ, the user is prompted for a valid Windows NT username and password. If the user provides invalid credentials, the server sends a Hypertext Transfer Protocol (HTTP) status code to the client browser indicating that access is denied unless some other authentication scheme is enabled.
NOTE
Internet Explorer 2 and later are the only Web browsers that currently support Windows NT Challenge/Response Authentication.
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You can configure IIS 4 so that basic authentication and Windows NT Challenge/Response Authentication are both available. When a browser that supports both methods makes a request to IIS 4 for authentication, Windows NT Challenge/Response Authentication takes precedence.
See also anonymous access, Basic Authentication
A command that can be typed at the Microsoft Windows NT command prompt, usually to perform an administrative action. You manage most Windows NT services by using GUI-based administrative tools, but some administrative tasks can also be performed at the command prompt. You can also save Windows NT commands in a text file and run them as a batch file.
Windows NT commands are grouped into several categories:
MS-DOS configuration commands: For configuring an MS-DOS environment to run MS-DOS applications. These commands include buffers, country, device, devichigh, dos, dosonly, driveparm, echoconfig, fcbs, files, install, lastdrive, ntcmdprompt, shell, stacks, and switches.
MS-DOS subsystem commands: For backward compatibility with MS-DOS applications. These commands include append, backup, debug, edit, edlin, exe2bin, expand, fastopen, graphics, loadfix, loadhigh, mem, nlsfunc, qbasic, setver, and share.
Windows commands: Include commands for administering and configuring aspects of the Windows NT operating system. Some of the more commonly used Windows commands are listed in this entry’s first table.
TCP/IP commands: Utilities associated with the TCP/IP protocol stack. These commands are listed in this entry’s second table.
OS/2 configuration commands: For configuring the operating system environment for applications that run using the OS/2 subsystem of Windows NT. These commands include codepage, devinfo, libpath, and protshell.
Net commands: For starting, stopping, and configuring networking services.
Batch commands: Used only within batch files for automating system tasks. These commands include call, echo, endlocal, for, goto, if, pause, rem, setlocal, and shift.
Filter commands: For sorting, viewing, and selecting portions of a command’s output. These commands include find, more, and sort.
Redirection symbols: For redirecting the input or output of a command to something other than standard input or output. These symbols include >, <, >>, and |.
Conditional processing symbols: Allow you to issue multiple commands from the same command prompt and to act based on the results of the commands’ execution. These symbols include &, &&, ||, ( ), and ^.
Windows Commands
| Command | Description |
| assoc | Displays or modifies file extension associations |
| at | Schedules commands and programs to run on a system at a specified time and date |
| attrib | Displays or changes file attributes |
| cacls | Displays or modifies the access control lists (ACLs) of files |
| chdir (cd) | Displays the name of the current directory or changes the current directory |
| chkdsk | Displays a disk status report and corrects errors on the disk |
| cls | Clears the screen |
| cmd | Starts a new instance of the Windows NT command interpreter |
| compact | Displays and alters the compression of files or directories |
| convert | Converts file allocation table (FAT) volumes to NTFS |
| copy | Copies one or more files to another location |
| date | Displays the date or allows you to change the date |
| del (erase) | Deletes specified files |
| dir | Displays a list of a directory’s files and subdirectories |
| diskcopy | Copies a floppy disk |
| diskperf | Starts and stops system disk performance counters |
| doskey | Calls the doskey program, which recalls Windows NT commands, edits command lines, and creates macros |
| exit | Quits the command interpreter and returns to the program that started it |
| format | Formats a disk to accept Windows NT files |
| help | Provides online information about Windows NT commands |
| mkdir (md) | Creates a directory or subdirectory |
| move | Moves one or more files to a specified directory |
| ntbooks | Accesses online Windows NT manuals |
| prompt | Changes the Windows NT command prompt |
| rename (ren) | Changes the name of a file or files |
| rmdir (rd) | Deletes (removes) a directory |
| start | Opens a separate window to run a program or a command |
| time | Displays the system time or sets the computer’s internal clock |
| tree | Displays the directory structure of a path or disk |
| type | Displays the contents of a text file |
| ver | Displays the Windows NT version number |
| vol | Displays the disk volume label and serial number |
| winnt | Performs an installation or upgrade of Windows NT 4 |
| winnt32 | Performs an installation or upgrade of Windows NT 4 |
| xcopy | Copies files and directories, including subdirectories |
TCP/IP Commands
| Command | Description |
| arp | Displays or modifies the IP-to-MAC-address translation tables |
| finger | Displays user information on a system running the finger service |
| ftp | Transfers files to or from a File Transfer Protocol (FTP) server |
| hostname | Prints the name of the current computer (host) |
| ipconfig | Displays current TCP/IP network configuration values |
| lpq | Obtains status of a print queue of a Line Printer Daemon (LPD) server |
| lpr | Prints a file to an LPD server |
| nbtstat | Displays protocol statistics and current NetBEUI TCP/IP (NBT) connections |
| netstat | Displays TCP/IP protocol statistics and connections |
| nslookup | Displays information from Domain Name System (DNS) name servers |
| ping | Verifies connections to a remote computer |
| rcp | Copies files to or from a system running rshd |
| rexec | Runs commands on remote computers running rexec |
| route | Displays or modifies network routing tables |
| rsh | Runs commands on remote computers running rsh |
| tftp | Transfers files to or from a system running tftp |
| tracert | Displays the route taken to a remote host on an internetwork |
NOTE
Microsoft Windows 2000 commands are essentially the same as those for Windows NT, with additional commands for services specific to Windows 2000.
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To see a list of all Windows NT commands and view their syntax, choose Help from the Start menu, select the Index tab, type commands , select Windows NT, and click Display.
See also net commands
A Microsoft Windows NT administrative tool useful for troubleshooting different aspects of system and network behavior. Windows NT Diagnostics can be used to display and print important configuration information for your computer running Windows NT Server. Windows NT Diagnostics can display
The operating system version and service packs applied
Processor and BIOS information
Display, drivers, and memory information
Installed services and their current states
Hardware settings such as interrupt request (IRQ), I/O port, and direct memory access (DMA) settings
System and user environment variables
Network interface card (NIC) settings, transports, and statistics
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On the Microsoft Windows 2000 platform, the equivalent of Windows NT Diagnostics is the System Information node in Computer Management.
The directory services used by Microsoft Windows NT to locate, manage, and organize network resources. Windows NT Directory Services (NTDS) uses domains, trusts, and directory synchronization to provide users of enterprise-level Windows NT networks with the following advanced capabilities:
Single-logon capability: Users can log on anywhere in the enterprise using only one account.
Centralized administration: Administrators can manage the entire network from a single location.
Universal resource access: Users can access resources anywhere in the enterprise if they have the appropriate permissions.
To build effective enterprise-level directory services using Windows NT domains, you should consider the following factors:
The number of domains needed (the domain model used)
The number of domain controllers needed to support the number of users
The placement of backup domain controllers (BDCs) to assure efficient directory synchronization of directory services
The placement of BDCs to assure effective logon and resource authentication over slow WAN links
See Distributed file system (Dfs)
A set of modules within the Microsoft Windows NT operating system that run in kernel mode and provide process structure, memory and object management, thread scheduling, interrupt processing, security, and other key operating system functions. The modules included in Windows NT executive are as follows:
I/O Manager
Object Manager
Security Reference Monitor
Process Manager
Local Procedure Call Facility (LPC Facility)
Remote Procedure Call Facility (RPC Facility)
Virtual Memory Manager
Win32K Windows Manager and GDI
Hardware device drivers
See also kernel mode
See Windows Explorer
See Windows NT Challenge/Response Authentication
An add-on software package for Microsoft Windows NT that includes Internet Information Server (IIS) version 4 and a number of supporting Microsoft BackOffice applications and tools, including the following:
Internet Connection Services for Microsoft Remote Access Service (RAS)
Microsoft Certificate Server
Microsoft Data Access Components (MDAC) 1.5
Microsoft FrontPage Server Extensions
Microsoft Index Server 2.0
Microsoft Management Console (MMC)
Microsoft Message Queue (MSMQ) Server 1.0
Microsoft Script Debugger 1.0
Microsoft Site Server Express 2.0
Microsoft Transaction Server (MTS) 2.0
See Windows NT
An enhanced version of the Microsoft Windows NT Server operating system. Windows NT Server, Enterprise Edition, includes the following features:
Windows NT Server 4: An enterprise-level network operating system that provides highly scalable file and print services, standards-based communication features, robust application support, and comprehensive Internet as well as intranet functionality.
4-GB RAM Tuning (4GT): An extension of the normal limit of addressable RAM available to applications in Windows NT Server. The 4 GB of RAM available in Windows NT Server are divided between applications and the kernel, each being allocated 2 GB. With 4GT, the potential RAM that can be allocated to the kernel is reduced to 1 GB, which leaves 3 GB for applications.
Eight-processor symmetric multiprocessing (SMP): Can be extended to up to 32 processors using original equipment manufacturer (OEM) versions of the product.
Microsoft Cluster Server (MSCS): Supports two-node cluster configurations that can automatically recover from application or server failures, allowing continuous availability of data and applications.
Microsoft Transaction Server (MTS): Provides an environment for developing and deploying scalable, enterprise-level Internet and intranet applications.
Microsoft Message Queue (MSMQ) Server: A service that enables applications to communicate asynchronously over heterogeneous networks.
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After you install Windows NT Server, Enterprise Edition, you can enable 4GT by adding the switch /3GB to the boot.ini file:
multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows NT Server Version 4.00" /3GB
An extension of the Microsoft Windows NT Server operating system for delivering Microsoft Windows to diverse desktop systems through terminal emulation. Windows NT Server, Terminal Server Edition, supports a broad range of clients, including the following:
Dedicated Windows-based terminals
Existing computers running 32-bit Windows
Older computers running 16-bit Windows
MS-DOS
Apple Macintosh, UNIX workstations, and other non-Windows platforms (using third-party add-ons)
Terminal Server can reduce costs because it supports a new class of low-cost hardware called Windows-based terminals. These hardware platforms are marketed by hardware vendors and contain an embedded terminal emulation client. Terminal Server also works with existing Windows desktop operating systems running on PCs; it runs the terminal emulation client as a window on the local desktop. Terminal Server is compatible with Windows applications from Microsoft such as Office, Internet Explorer, Exchange, Outlook, and Project, as well as Microsoft Visual Basic–based applications and many other popular 32-bit Windows applications.
You can use Terminal Server to deploy a thin-client solution that eliminates the need to download applications from the server. The Terminal Server client has only minimal software for booting the client, connecting to the server, and displaying the Windows interface to the user. All operating system functions and applications run entirely from the server. Terminal Server provides a host-based computing environment in which administrators can manage all server resources on a per-user basis. It supports a multiuser environment in which a terminal emulator displays a Windows desktop and Windows-based applications that actually run completely off the server.
Terminal Server has four main components:
Terminal Server server software
Terminal Server Client software
Remote Desktop Protocol (RDP), which is based on the T.120 protocol developed by the International Telecommunication Union (ITU)
Administration Tools, including Terminal Server License Manager, Terminal Server Client Creator, Terminal Server Client Connection Configuration, and Terminal Server Administration tools
See also Windows NT
See Windows NT
A language-independent scripting host included with Microsoft Windows 2000, Windows NT Option Pack, and Windows 98 that allows administrators to execute scripts for administrative tasks either from the command console (using cscript.exe) or by double-clicking on a desktop shortcut (using wscript.exe). Administrative scripts can be written in Microsoft Visual Basic, Scripting Edition (VBScript), or in Microsoft JScript and can be written to perform common or repetitive administrative tasks such as performing a backup, creating new users, and configuring clients. Windows Script Host (WSH) allows these scripts to be run without being embedded in a Hypertext Markup Language (HTML) document. You can also add support for other scripting languages, such as Perl or REXX.
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You can configure how scripts are run by using .wsh files, which are created automatically when you access the properties of a VBScript or JScript file on a system with WSH installed. These .wsh files act like INI files, enabling you to configure settings such as how long a script should be allowed to run before being terminated. You can create a series of different .wsh files for a given script and use these in different situations. Double-click on a .wsh file to run the associated script.
Also called Winsock, an interprocess communication (IPC) mechanism that provides reliable, connection-oriented two-way communication or unreliable connectionless communication between processes on two computers. Windows Sockets is a Microsoft Windows implementation of the well-known Berkeley Sockets application programming interface (API) for accessing datagram and session services over TCP/IP. It provides guaranteed delivery of data between computers for distributed applications.
Windows Sockets can be used by TCP/IP, NWLink, and AppleTalk network protocols. Windows Sockets applications on Windows operating systems include File Transfer Protocol (FTP), Telnet, and Microsoft Internet Explorer. Windows Sockets is implemented as a dynamic-link library (DLL) for Windows operating systems. The current implementation of Windows Sockets on Windows platforms is version 2, which supports multicasting, provides better performance than previous versions, and supports wireless communication.
An Internet-based tool for locating and installing updates and enhancements to the Microsoft Windows 2000 and Windows 98 operating systems. Windows Update can be thought of as an online extension of Microsoft Windows, and is designed to help you get the most out of your computer.
How It Works
You need to establish an Internet connection in order to use Windows Update. You open Windows Update by selecting its shortcut from the Start menu. This action starts Microsoft Internet Explorer and takes you to a page on the Web site http://windowsupdate.microsoft.com. Note that you must be an administrator or a member of the Administrators group to access the Product Updates section of the Windows Update Web site. Once you have connected to the site, ActiveX controls scan your system for outdated system files and determine which new versions of these files should be installed. These system files can include drivers, patches, help files, or new Windows components you can download to keep your computer up-to-date.
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You also have the option of restoring previous versions of system files that have been changed by Windows Update. To do this, start Windows Update, go to Product Updates, select Device Drivers, and click Restore.
The Setup program for installing Microsoft Windows NT or Windows 2000 on computers with a non–Windows NT operating system such as MS-DOS, Microsoft Windows 95, or Microsoft Windows 98. Winnt.exe is in the \I386 directory on the Windows NT 4 Server CD or Windows 2000 Server CD. The following table describes three common switches for this program.
Common Switches for Winnt.exe
| Switch | Description |
| /b | Installs Windows NT or Windows 2000 without using the three Windows NT boot floppies. Use this switch to install Windows NT on systems with a non–Windows NT operating system (such as Windows 95 or Windows 98). |
| /ox | Creates the three Windows NT boot floppies. Does not install Windows NT or Windows 2000. |
| /u | Performs unattended installation. |
NOTE
The Setup program for installing Windows NT 4 or Windows 2000 on systems with a version of Windows NT already installed is winnt32.exe. You can use winnt32.exe to upgrade earlier versions of Windows NT to Windows NT 4 or Windows 2000, or to install a second copy of Windows NT 4 or Windows 2000 to a different system folder if you are attempting to recover from a system crash.
See Windows Internet Name Service (WINS)
A client operating system that can register its NetBIOS name with a WINS server. It’s also known as a WINS-enabled client. All Microsoft operating systems that are network-capable can be WINS clients. You can configure Microsoft Windows NT, Windows 2000, Windows 98, and Windows 95 clients by doing one of the following:
Manually configuring the IP address of the WINS servers by using the WINS Address tab of the TCP/IP property sheet (or Advanced TCP/IP Settings in Windows 2000).
Using the Dynamic Host Configuration Protocol (DHCP) with DHCP scope option 44 to configure DHCP clients as WINS clients. In Windows NT you do this by using the administrative tool called DHCP Manager, while in Windows 2000 you use the DHCP console.
NOTE
For non-WINS clients such as Macintosh computers, you can use the WINS proxy agent (provided with Windows NT and Windows 2000) to enable these clients to perform NetBIOS name resolution. You can also configure static mappings on the WINS server to enable these non-WINS clients to be resolved using NetBIOS name resolution.
See also Windows Internet Name Service (WINS)
See Windows Sockets
A computer on a network that enables non-WINS clients to perform NetBIOS name resolution using Windows Internet Name Service (WINS). In other words, a WINS proxy agent is a proxy for, and acts on behalf of, non-WINS clients. WINS proxy agents are typically only needed on networks that have client computers running legacy operating systems.
How It Works
WINS proxy agents are computers that have been configured to listen for NetBIOS name registration and NetBIOS name discovery broadcasts from non-WINS clients and then forward these broadcasts directly to a WINS server. These non-WINS clients are computers that cannot communicate directly using WINS and typically use broadcasts only (B-node) to perform NetBIOS name registration and resolution.
For example, if a non-WINS or B-node client wants to register its name on the network, it broadcasts a NetBIOS name registration request. The proxy agent detects this broadcast request and forwards it directly to the WINS server, which checks its WINS database to see whether the NetBIOS name is already being used on the network. If the name is in use, the WINS server responds to the proxy agent with a negative registration response, and the proxy server forwards this response back to the B-node client indicating that the name is already in use on the network.
You can configure computers running Microsoft Windows NT Server and Windows 2000 Server to operate as Windows proxy agents by making changes to their registries. Specifically, to enable a computer running Windows NT or Windows 2000 to act as a WINS proxy agent, use regedit to set the value EnableProxy equal to 1 for the following key:
HKEY_LOCAL_MACHINE \System \CurrentControlSet \Services \NetBT \Parameters
NOTE
WINS proxy agents must be WINS clients but cannot be WINS servers.
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WINS proxy agents are needed only on those subnets that have both of the following characteristics:
No WINS server
Include non-WINS clients that need to be able to resolve the names of NetBIOS computers on other subnets
A resource record within a zone file that identifies a host on the network as a WINS server on the network. WINS records are used in Microsoft Windows NT–based networks to enable Domain Name System (DNS) servers to refer name lookups to WINS servers. On Windows NT–based networks, WINS uses a dynamically updated database, while the DNS database is static and needs to be manually configured. DNS is thus harder to manage than WINS on Windows NT. So by configuring DNS to use WINS wherever possible, you simplify administration of name resolution on the network.
WINS records are specific to Microsoft’s implementation of DNS on Windows NT and are not used with the new dynamic update of Windows 2000 or in non–Microsoft Windows networks such as those using BIND running on UNIX servers.
See also Domain Name System (DNS), resource record
A Microsoft Windows NT–based or Windows 2000–based server running the Windows Internet Name Service (WINS) that can accept NetBIOS name registrations and queries. WINS servers maintain a database of NetBIOS name to IP address mappings for WINS clients on the network and speed up NetBIOS name resolution by eliminating broadcasts.
How It Works
NetBIOS over TCP/IP clients configured as H-node clients register their names with a WINS server when they are initialized on the network. The WINS server maintains a database called the WINS database, which stores the NetBIOS name to IP address mappings for all hosts on the accessible network. Periodically, one of the hosts must renew its name registration for all its NetBIOS-enabled services. When a host is properly shut down or when a NetBIOS-related service is stopped on the host, the associated NetBIOS names are released from the WINS database. When a host tries to contact another host using NetBIOS over TCP/IP, a NetBIOS name query request is sent to the WINS server, which returns the IP address of the host and thus allows communication to take place.
WINS servers replicate the WINS database with other WINS servers to keep the database entries up-to-date. You can configure WINS servers for two replication roles:
Push partners send notices to their pull partners, notifying them of a certain threshold number of changes to their WINS database. You can configure this number on the push partners by using the Windows NT administrative tool WINS Manager or the WINS console in Windows 2000. The pull partners respond by requesting the changes, which the push partners then send.
Pull partners periodically send requests to their push partners, asking if any changes have been made to their WINS database. You can configure the time interval for sending these requests on the pull partner. The push partners respond by sending the changes.
NOTE
WINS servers should have static IP addresses assigned. You can create static mappings to allow non-WINS clients on the network to be resolved, and you can use WINS proxy agents to allow non-WINS clients to perform name resolution.
When you configure WINS replication, you should consider the following:
You can configure WINS servers to be both push and pull partners with other WINS servers.
WINS servers replicate only changes, not the full WINS database.
On Windows NT WINS servers, you can manually force WINS replication by clicking the Replicate Now button in WINS Manager. On Windows 2000 WINS servers, you use the Action menu in the WINS console.
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For fault tolerance on large networks, you should consider using a second WINS server, with WINS replication configured between the primary WINS server and secondary WINS server. One primary and one secondary WINS server are recommended for every 10,000 WINS clients on the network.
Over local area network (LAN) or high-speed wide area network (WAN) links, you should configure all WINS servers as both push and pull partners to keep the WINS database up-to-date on all WINS servers. Over slow WAN links, however, you should configure WINS servers as pull partners only so that you can schedule replication when WAN traffic is light.
See also NetBIOS name resolution, Windows Internet Name Service (WINS)
A set of technologies developed by a consortium of mobile telephony equipment vendors that is designed to bring Web content to wireless handheld communication devices such as Personal Digital Assistants (PDAs) and mobile phones. These devices are too small to easily display or allow users to interact with regular Web content. Wireless Application Protocol (WAP) enables them to receive simplified versions of regular Web pages. Typical uses for WAP-enabled devices might be to access stock market information, perform online banking, access inventory and sales information for sales quotes, and exchange information with business partners.
Graphic W-13. Wireless Application Protocol (WAP).
WAP is part of the Mobile Station Application Execution Environment (MExE) initiative from the European Telecommunications Standards Institute (ETSI) and is currently being tested by companies such as Alcatel, Nokia, and APiON.
How It Works
The WAP protocol stack lies within layers 4, 5, 6, and 7 of the Open Systems Interconnection (OSI) reference model for networking. For addressing and routing purposes, WAP uses the same layer 3 (network layer) protocol as TCP/IP, namely the Internet Protocol (IP). This allows WAP-enabled devices to request and receive Web content from the Internet by using the Hypertext Transfer Protocol (HTTP). However, instead of using the connection-oriented Transmission Control Protocol (TCP), WAP uses the connectionless User Datagram Protocol (UDP) for layer 4 (transport layer) session establishment because UDP has less overhead than TCP and is thus more suitable for the limited transmission capabilities of wireless handheld devices.
WAP uses the Wireless Transaction Protocol (WTP) instead of HTTP for its connectionless layer 7 (application layer) protocol. In addition, WAP-enabled devices can display only content that is formatted using Wireless Markup Language (WML), a simplified version of Hypertext Markup Language (HTML) for handheld wireless devices that includes limited display capabilities.
To request Web content from the Internet, a WAP-enabled device makes a WTP request to a WAP gateway, a device that stands between the WAP devices and Web sites. The WAP gateway services the WTP request in one of two ways:
The WAP gateway can itself host Web sites formatted in WML and return this content directly to the WAP device. The disadvantage of this method is that content providers must develop redundant versions of HTML-formatted Web sites in WML.
The WAP gateway can translate the WTP request that it received using UDP into an HTTP request contained in TCP packets and forward this HTTP request to a regular Web server on the Internet that hosts HTML-formatted Web content. The Web server returns the content to the WAP gateway using TCP, which translates the HTML into WML and sends it to the WAP device using UDP. This is the normal operation of a WAP gateway. Web content developers need only create one version of their site in HTML, although they must ensure that the page looks satisfactory when translated into WML.
WAP gateways can also be configured for other uses, such as collecting personal information from customers and recording traffic for billing purposes.
NOTE
WAP is designed primarily to enable Web content to be delivered over wireless communication systems, which are characterized by low speed and variable delays. Caching can be implemented on wireless handheld devices to minimize the amount of information that needs to be downloaded, but memory limitations currently prevent this from being very effective. You can use TCP header compression to reduce headers to only 3 or 4 bytes to speed up standard TCP/IP connections with these devices in order to boost performance a bit. You can adjust the TCP retransmission parameters to compensate for the typical round-trip time of 100 milliseconds to several seconds when users move through cells in wireless communication networks. But the TCP window size negotiation algorithm to optimize TCP transmission generally works poorly in situations where the typical delay varies so frequently and greatly. You can use middleware between the WAP device and the application server to simplify and streamline the data being transferred. Nevertheless, WAP has growing support in the cellular industry, especially because it shifts vendors toward the role of content hosting and development, which is a lucrative add-on in light of falling cellular line charges.
On the Web
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WAP Forum : http://www.wapforum.org
Networking that uses electromagnetic waves traveling through free space to connect stations on a network. Wireless transmission is said to use unguided media, as opposed to the guided media of copper cabling and fiber-optic cabling used in traditional wired networks. Wireless networking is typically used for
Communication with mobile stations, which precludes the use of fixed cabling, or for mobile users who roam over large distances, such as sales reps with laptops that have cellular modems.
Work areas in which it is impractical or expensive to run cabling, such as older buildings that are costly to renovate. In this case, two solutions are possible:
Create a wireless LAN (WLAN) that uses no cabling between stations.
Create a combination of traditional wired local area networks (LANs) and as many wireless stations as needed.
Networking buildings on a campus using a wireless bridge or router. You can typically use wireless bridges or routers over distances up to 25 miles. They might support point-to-point or multipoint connections and often support Internet Protocol (IP) or Internetwork Packet Exchange (IPX) routing using static routing or the Routing Information Protocol (RIP).
Wireless networking suffers somewhat from lower data transmission rates (the maximum is currently about 10 Mbps), greater susceptibility to electromagnetic interference (EMI), and greater risk of eavesdropping than transmission over guided media. You can largely solve the security issue by using secure network protocols, but you should be sure to isolate wireless stations from sources of EMI in the operating frequency range of the network. A microwave oven, for example, can degrade wireless communication that is based on the microwave portion of the electromagnetic spectrum.
How It Works
In the broadest sense, wireless networking is composed of all forms of network communication that use electromagnetic waves of any wavelength or frequency, which includes the following portions of the electromagnetic spectrum:
Infrared (IR): Ranges from frequencies of about 300 GHz to 200 THz and is used primarily in confined areas where line-of-sight communication is possible. IR cannot penetrate buildings or structures, but it can reflect off light-colored surfaces.
Microwave: Ranges from 2 GHz to 40 GHz and is used for both point-to-point terrestrial communication and satellite communication. Microwave suffers from signal degradation when weather conditions are poor (for example, in fog or rain).
Broadcast radio: Ranges from 30 MHz to 1 GHz, is less affected by poor atmospheric conditions than microwave, and can travel through most buildings and structures, but suffers from multipath interference over long distances.
To connect wireless stations to a traditional wired LAN, you need only two components:
One or more access points, which are transceivers connected to the wired LAN. They broadcast signals to and receive signals from the wireless stations on the LAN, forwarding signals between the wired network and the wireless stations as needed. The effective reception range from an access point defines a circular area called a cell, or more properly, a Basic Service Set. When more than one access point exists on a network and their cells overlap, the access point devices must also hand off communication as roaming stations move from one cell to another. The number of wireless stations that an access point can effectively handle is inversely proportional to the average traffic generated by each station. A typical wireless access point device might provide up to 3000 square meters of coverage in open areas (or less when obstacles are present) and support data transmission rates of 1 to 10 Mbps.
A WLAN adapter, which can be an external device called a station adapter that plugs into the RJ-45 port of a 10BaseT Ethernet card, an external device that connects to an RS-232 serial port, or a special PCMCIA card. Whatever configuration you use, the wireless adapter turns the computer in which it is installed into a wireless station on the network. A fixed or detachable antenna is generally included and gives the station better transmission and reception. For a small-scale WLAN, the typical power output for an adapter might be 100 mW, resulting in a coverage range of about 305 meters in open areas (or less when obstacles are present).
Graphic W-14. Wireless networking.
The existing standard for wireless networking is IEEE 802.11 of Project 802, which specifies the physical layer (PHY) and media access control (MAC) protocols and characteristics for wireless communication between networked stations. In particular, 802.11 covers low-power wireless microwave communication in the Industrial, Scientific, and Medial (ISM) communication band centering on 2.4 GHz that was set aside by the Federal Communications Commission (FCC) in the early 1980s for unlicensed wireless communication. 802.11 covers both common spread spectrum communication methods (direct sequencing and frequency hopping), includes an exportable encryption algorithm called wired equivalent privacy (WEP) to prevent eavesdropping, and specifies a maximum data transmission speed of either 1 or 2 Mbps. 802.11 also specifies standards for wireless communication using infrared light. 802.11 is currently being revised to support transmission speeds of up to 20 Mbps.
NOTE
Both direct sequencing spread spectrum (DSSS) and frequency hopping spread spectrum (FHSS) wireless technologies can operate in the unlicensed 2.4-GHz ISM band. DSSS equipment is also available for operation in a portion of the 900-MHz frequency band—the same part of the electromagnetic spectrum used by Cellular Digital Packet Data (CDPD) cellular telephone and Personal Communications Services (PCS) paging technologies—and is better able to penetrate buildings and structures than 2.4-GHz equipment. When you use a wireless bridge, 900 MHz is preferred for longer distances; 2.4 GHz works better over shorter distances and provides greater network throughput.
Most wireless systems use the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) media access method, in contrast to the Carrier Sense Multiple Access with Collision Detection (CSMA/CD) method used in wired Ethernet networks. The primary reason for this is that it is difficult to detect collisions between unguided electromagnetic waves.
TIP
Use an omnidirectional antenna if your wireless bridge or router is being used for point-to-point communication.
Also called an equipment room or server room (and various other names), a room on the floor of a building that contains hubs, switches, and other network components for the floor that is connected through a vertical backbone cable to the main equipment room, which is usually in the basement of the building (in a multifloor building). The wiring closet for a floor is the termination point for horizontal cabling running from wall plates in work areas on that floor. This horizontal wiring typically terminates in a series of patch panels in the wiring closet. Patch cables are used to connect jacks on the patch panels to ports on hubs and switches to establish network connectivity between computers on the floor and with other floors. In a single-floor building, the wiring closet and the main equipment room are the same and are sometimes called the telecommunications closet because telecommunications services typically terminate in that room as well.
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The EIA/TIA wiring standards recommend one wiring closet per floor, with a minimum size of 3 meters by 2 meters for up to 455 square meters of floor space. When stations must be located more than 91 meters from the wiring closet, additional wiring closets are recommended. Wiring closets should be well-lit and have adequate power supply. Equipment should be mounted on racks for greater security and efficiency. “Spaghetti” should be minimized—keep everything accurately labeled to save yourself hours of troubleshooting time when things go wrong. Keep access to the wiring closet clear and secure, and include fire protection devices.
See also premise cabling
See Windows Management Instrumentation (WMI)
The result of the first stage of the indexing process in Microsoft Indexing Service. Word lists are temporary indexes stored in RAM in a relatively uncompressed state. They are a staging ground for the generation of more efficient indexes called persistent indexes. When the amount of word lists exceeds a specified number, they are merged together.
See also Indexing Service
A logical grouping of networked computers that can share resources with each other. These resources might include files, printers, and other devices. A workgroup is often called a peer-to-peer network because all computers in a workgroup are equally important. In other words, no single computer “runs the network,” as in a domain-based model.
How It Works
Each computer in a workgroup handles security separately using its own local security database, which tracks who can log on to the computer and what rights or permissions users have to resources on the computer. A user who wants to log on to a computer must have an account in that computer’s local security database. A user with an account on one computer doesn’t necessarily have any permissions or rights to resources on other computers.
If a computer in a workgroup is used to provide file, print, or other resources to other computers in the workgroup, that computer is generally called a peer server or a stand-alone server. Because security is local to each computer in a workgroup, a peer server can share resources using share-level security only, which uses passwords to protect access to each resource. Users who know this password can access the resources at the level of access with which it is shared (such as read-only access, full access, and so on).
Workgroups are simple to implement but hard to maintain. Administrators must create accounts on each computer for the users who need access to them. As a result, workgroups are generally used for small networks of 10 or fewer computers in which security and centralized administration are not an issue.
The physical memory assigned to a process by the Microsoft Windows NT and Windows 2000 operating systems. The working set consists of pages, which are sections of code and application data that have recently been used by the process. If the process requires code or data that is not in its working set, it generates a page fault, causing the Virtual Memory Manager to swap new pages into the working set. If page faults become excessive, application performance can be slowed. Adding more RAM is one solution to this problem, while increasing the maximum working set size can also be helpful.
If memory becomes scarce, the Virtual Memory Manager moves the memory pages referenced less recently from the working sets in order to recover memory for the system. Older pages are also removed as new pages are added. Efficient applications use and store data in sequence, with the result that fewer memory pages are needed by the application, allowing a small working set.
Also known as LanmanWorkstation, a component of the Microsoft Windows NT and Windows 2000 operating systems that allows a client to request file and print resources from servers over the network.
How It Works
The Workstation service is a user mode service that works together with a kernel mode component called the redirector file system driver, or rdr.sys. This redirector is implemented as a standard file system driver and resides above the Transport Driver Interface (TDI) layer, which allows it to interact independently with any transport protocols.
The Workstation service on a client computer accepts an input/output (I/O) request for a remote file, named pipe, or mailslot; determines which service can best provide this resource; and redirects the request to the Server service on the server where the requested resource resides. The Server service provides the requested resource and routes it back to the client that requested it. The Server service also consists of two components, a user mode component called LanmanServer and a kernel mode component called the server file system driver, or srv.sys.
You can also install additional redirectors from third-party vendors that can coexist with the Workstation service on Windows NT and Windows 2000. An example of an additional redirector included with Windows NT and Windows 2000 is Gateway Service for NetWare (GSNW), which enables Microsoft Windows clients to gain access to files and printers on a Novell NetWare server.
See also Server service
The most popular of Internet services, rapidly changing the way business is done around the world. The World Wide Web Consortium (W3C) defines the World Wide Web (WWW, or Web) as “the universe of network-accessible information, the embodiment of human knowledge.” The WWW began as a project for sharing hypertext information over a network that was developed by Tim Berners-Lee at CERN, a physics research center in Geneva, Switzerland.
How It Works
The Web consists of all client and server applications that communicate over the Internet using the client/server protocol Hypertext Transfer Protocol (HTTP), as well as the resources that reside on those servers and are accessed by those clients. These resources are generally referred to as “Web sites” and consist mainly of text files formatted in Hypertext Markup Language (HTML) and associated image, sound, multimedia, script, and other files. Each HTML file is called a Web page (or page), and pages in a site are generally linked in a hierarchical fashion, starting with the home or top page, using anchor tags. Web sites are stored on Web servers, which run software that handles the server side of HTTP, such as Internet Information Services (IIS) for Microsoft Windows 2000. Users access Web sites on the Internet by using client software, typically called a Web browser (such as Microsoft Internet Explorer).
See also Hypertext Transfer Protocol (HTTP)
A vendor-neutral organization created in 1994 that develops common, interoperable protocols for the World Wide Web (WWW). Represented by the Massachusetts Institute of Technology (MIT) in the United States and a number of international research centers, the World Wide Web Consortium (W3C) provides a variety of services to its member organizations, including the following:
Discussion groups and meetings on issues relating to the evolution of the WWW
Repositories of information, reference documents, and code relating to WWW protocols, services, and applications
The creation and testing of applications that demonstrate new types of WWW technologies
The director of the W3C is Tim Berners-Lee, the creator of the WWW. Membership in the W3C is tailored to organizations, but individuals can become affiliate members for an annual fee. For additional information about the WWW, you can subscribe to the World Wide Web Journal, produced by O’Reilly & Associates.
On the Web
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W3C home page : http://www.w3c.org
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World Wide Web Journal : http://www.w3j.com
A component of Internet Information Services (IIS) on Microsoft Windows 2000 and of Internet Information Server (IIS) on Microsoft Windows NT. The World Wide Web Publishing Service provides support on Windows 2000 and Windows NT for communication using the Hypertext Transfer Protocol (HTTP). This protocol allows users to publish Web content on IIS for use on the Internet or on corporate intranets. Published Web content can then be accessed and displayed on client computers by using a standard Web browser such as Microsoft Internet Explorer. The World Wide Web Publishing Service is also central to third-party applications that facilitate remote administration of computers running Windows 2000 and Windows NT using Web browsers as their standard administrative interface.
See also Hypertext Transfer Protocol (HTTP), Internet Information Services (IIS)
Stands for “Win16 on Win32,” a component of the Microsoft Windows NT operating system that enables 16-bit Microsoft Windows applications (such as those designed to run on Windows 3.1 and Windows for Workgroups 3.11) to run properly on Windows NT’s 32-bit operating system.
How It Works
Like MS-DOS applications, 16-bit Windows applications (Win16 applications) also run on Windows NT within the context of a Windows NT Virtual DOS Machine (NTVDM), which simulates the 16-bit environment necessary for these applications to run. However, while MS-DOS applications each require their own separate NTVDMs in which to run, Win16 applications run within a single NTVDM called WOW, which corresponds to the system process wowexec.exe. And while NTVDMs hosting MS-DOS applications are single-threaded, WOW is a multithreaded NTVDM in which each Win16 application runs as a separate thread using the same shared address space. WOW also simulates the cooperative multitasking environment for which applications written for Windows 3.1 and Windows for Workgroups 3.11 are designed. WOW will allow only one Win16 application to run at a time, blocking the threads of all other Win16 applications until the running application relinquishes control. If the Windows NT kernel needs to preempt the Win16 application (by preempting WOW), it always resumes with the same Win16 application.
WOW also handles the translation of 16-bit Windows application programming interfaces (APIs) and messages to their corresponding 32-bit APIs and messages, enabling interoperability and data sharing between 16-bit and 32-bit Windows applications on the Windows NT platform.
NOTE
WOW starts automatically when the first Win16 application is started on the Windows NT system.
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Windows NT also includes an option for running Win16 applications in their own separate NTVDMs, which enables Win16 applications to function as a process within Windows NT’s preemptive, multitasking environment. You can run a Win16 application in a separate NTVDM by opening the Run box from the Start menu, typing the path to the Win16 executable, and selecting the Run In Separate Memory Space check box. Note that doing this can have negative effects on Win16 applications that need to share data with each other by using legacy data-sharing mechanisms such as Dynamic Data Exchange (DDE).
See Windows Script Host (WSH)
See World Wide Web (WWW)
