Interactive-Internet Fax Protocol

Interactive

The ability of a person or device to talk to or communicate with another device (typically a computer) in real time, i.e. no delays. The term generally is applied in the context of interaction with a computer over a network in a conversational mode. Interactive processing is very time-dependent since a user is sitting there, waiting for the computer to ask him/her questions. The opposite of Interactive processing is batch processing. See Batch and Real Time.

Interactive CATV

Interactive CATV is a two-way cable system from which subscribers can receive and send signals. They will probably do this by punching buttons on their cable TV's remote control, which may look more like a computer keyboard than a traditional cable TV handheld remote signaling device.

Interactive Data Transaction

A single (one-way) message, transmitted via a data channel to which a reply is required for work to proceed logically.

Interactive Kiosk

Interactive kiosks represent a powerful new product delivery vehicle for "non-store" marketers, to increase sales by offering their products and services in high traffic areas, such as airports. According to research analyst Warren Hersch, financial services kiosks are not confined to full-service bank locations; they are found in supermarkets, shopping malls and auto dealerships. Self-service terminals offering government services reside in discount stores, libraries, outdoor pavilions and subway stations . Kiosks purveying travel- related services occupy office complexes, colleges and universities, pharmacies and other retail outlets.

Interactive logon

Logging onto a machine via the keyboard, in contrast to a network logon.

Interactive Processing

A computer operation in which each item is processed as it is entered (on a time scale of seconds). An example is automatic teller machines (ATMs).

Interactive Services

A B-ISDN term referring to two-way communications in support of three types of services. "Conversational Services" include interactive voice, video and data communications. "Messaging Services" include video mail and compound mail. "Retrieval Services" include retrieval of data, image, video, and compound mail documents. Most of these services are highly bandwidth- intensive , hence their inclusion in the concept of Broadband ISDN.

Interactive Television Association

ITV has now changed its name to the Association for Interactive Media (AIM). See AIM.

Interactive Video

The fusion of video an computer technology. A video program and a computer program running in tandem under the control of the user. In interactive video, the user's actions, choices, and decisions affect the way in which the program unfolds. See Indeo Video.

Interactive Video and Data Service

IVDS. See 218-219 MHz.

Interactive Voice Response

IVR. Think of Interactive Voice Response as a voice computer. Where a computer has a keyboard for entering information, an IVR uses remote touchtone telephones. Where a computer has a screen for showing the results, an IVR uses a prerecorded human voice that is stored (digitized) on a hard drive. In addition it can use a synthesized voice (computerized voice) for read back information that is constantly changing. (The synthesized voice is commonly referred to as Text-to-Speech.)

Whatever a computer can do, an IVR can too, from looking up train timetables to moving calls around an automatic call distributor (ACD). The only limitation on an IVR is that you can't present as many alternatives on a phone as you can on a screen. The caller's brain simply won't remember more than a few. With IVR, you have to present the menus in smaller chunks . See IVR.

Interagency Interim National Research and Education Network

See IINREN.

Interagency Radio Advisory Committee

IRAC. A government committee that advises the Commerce Secretary on the government's spectrum needs.

Interarea Cell Transfer

A cellular radio term. A cell transfer between two cells that are controlled by different serving Mobile Data Intermediate Systems (MD-ISs).

Interaxial Spacing

Center to center conductor spacing between any two wires.

Interbreak Interval

A call center term. A Scenario scheduling assumption specifying the minimum amount of time that must elapse between the end of one break and the beginning of another.

Interbuilding Backbone

Telecommunications cable(s) that are part of the campus subsystem that connect one building to another.

Interbuilding Cable

The communications cable that is part of the campus subsystem and runs between buildings . There are four methods of installing interbuilding cable: in-conduit (in underground conduit), direct-buried (in trenches), aerial (on poles), and in- tunnel (in steam tunnels).

Interbuilding Cable Entrance

The point at which campus subsystem cables enter a building.

Interbuilding Wiring

Consists of underground or aerial telephone wire/cables used on the premises to connect structures remote from the primary building to the premises telephone system.

Intercast

New plug-in cards from Intel which will allow your PC to simultaneously receive TV pictures, and in the blank spaces of TV signals, Internet Web pages and text.

Intercept

Calls which cannot reach their destination may be intercepted and diverted to a station attendant, a recording or some other place. See Intercept Recording and Intercept Service.

Intercept Interval

A telephone company term. The intercept interval is the amount of time a changed or disconnected telephone number must remain unassigned in order to insure that after reassignment the new customer does not receive calls intended for the previous subscriber. Intercept intervals vary by customer class of service and are established by the utilities commissions and/or telephone companies.

Intercept Recording

You make a phone call. It doesn't go through. The phone company intercepts that call and sends it somewhere. Intercept Recording is a recording telling you your call cannot be completed and has been intercepted on its way to the destination number for some reason that will be explained by the recording. The most common voice you hear on intercept announcements is Jane Barbie's. See Barbie, Jane and Intercept Service.

Intercept Operator

A person who provides intercept service at an intercept position of a switchboard or at an auxiliary services position of a centralized intercept bureau .

Intercept Service

A service of the local phone in which a phone call is redirected by an operator or a recording to another phone number or a message.

Interchange Carrier

IC. A common carrier that provides services to the public local exchanges on an intra or interLATA basis in compliance with local or Federal regulatory requirements and that is not an end user of the services provided.

Interchangeable NPA Code

Code in the NXX format used as a central office code (NNX format), but that can also be used as an NPA code. Interchangeable NPA codes will be introduced on or after January 1, 1995.

Intercom

Intercommunication. An internal communication system which allows you to dial another phone in your building, office complex, factory or home. There are three types of intercom:

1. Dial: It allows you to dial or pushbutton another extension;

2. Automatic: One phone goes off hook and automatically dials another; and

3. Manual: The user can manually signal another phone by pushing a button for that phone. An example is a buzzer between a boss and a secretary.

Intercom Blocking

A PBX feature by which phones with a particular Class Of Service (COS) are blocked from calling certain phones. A rare feature.

Interconnect

A circuit administration point, other than a cross connect or an information outlet, that provides capability for routing and re-routing circuits. It does not use patch cords or jumper wires, and typically is a jack-and-plug device used in smaller distribution arrangements or that connects circuits in large cables to those in smaller cables. See Interconnect Companies.

Interconnect Agreement

An agreement between an established local phone company and a new local phone company for both companies to allow their subscribers to dial each other. Such agreement covers issues such as sharing of revenues and if a subscriber, who changes local phone companies, can keep his phone number.

Interconnect Companies

Companies which sell, install and maintain telephone systems for end users, typically businesses. AT&T coined the word "interconnect" as a pejorative word ” to indicate that these companies " interconnected " to AT&T's telephone network ” but didn't really belong there and, if they were there, they were probably unreliable. These "interconnect" companies contrasted with true-blue companies belonging to AT&T which did a sterling job. Anyway, despite the changes in the industry, the term stuck and the nasty associations have pretty well gone away. Now the irony is that the independent (i.e. non-Bell, non-AT&T) interconnect companies often deliver better service at a lower price. The industry is looking for a better word. TELECONNECT Magazine once started a campaign to make "TELECONNECT" a replacement for interconnect. But TELECONNECT's lawyers and the lawyers for a manufacturing/interconnect company called Teleconnect told us to lay off and stop trying to make the word generic. Since then we rather like the terms "Telecommunications Systems Integrator," "Telecommunications VAR" or "Telecom Developer." They seem to be catching on.

Interconnection

A term generally used to describe the connection, with or without a protective connecting arrangement, of customer- or phone company-provided communications equipment to facilities of the local phone companies.

Interdiction

In cable television networks, one method of denying a subscriber the reception of those (premium) channels that are not ordered and paid for. As such, interdiction is one option in a conditional access strategy. Special filters or scramblers on a subscriber drop usually perform interdiction, which block or garble the premium channel or channels.

Interdomain Trust Relationships

With Windows NT, Unix and some other operating systems, the user accounts and global groups from one domain can be used in another domain. In the MIS world, a domain is the part of a computer network in which the data processing resources are under common control. In the Internet, a domain is a place you can visit with your browser ” i.e. a World Wide Web site. When a domain is configured to allow accounts from another domain to have access to its resources, it effectively trusts the other domain. The trusted domain has made its accounts available to be used in the trusting domain. These trusted accounts are available on Windows NT Server computers and Windows NT Workstation computers participating in the trusting domain.

Hint: By using trust relationships in your multidomain network, you reduce the need for duplicate user account information and reduce the risk of problems caused by unsynchronized account information.

The trust relationship is the link between two domains that enables a user with an account in one domain to have access to resources on another domain. The trusting domain is allowing the trusted domain to return to the trusting domain a list of global groups and other information about users who are authenticated in the trusted domain. There is an implicit trust relationship between a Windows NT Workstation participating in a domain and its PDC.

In this example, the following statements are true because the London domain trusts the Topeka domain:

Users defined in the Topeka domain can access resources in the London domain without creating an account within that domain. Topeka appears in the From box at the initial logon screen of Windows NT computers in the London domain. Thus, a user from the Topeka domain can log on at a computer in the London domain. When trust relationships are defined, user accounts and global groups can be given rights and permissions in domains other than the domain where these accounts are located. Administration is then much easier, because you need to create each user account only once on your entire network, and then the user account can be given access to any computer on your network (provided you set up domains and trust relationships to allow it).

Note Trust relationships can be configured only between two Windows NT Server domains. Workgroups and LAN Manager 2.x domains cannot be configured to use trust relationships.

Interdrive

The name of the FTP Software client implementation of the Sun NFS protocol.

Interend Office Trunk Groups

A category of trunk groups that interconnects end offices.

Interenterprise Communications

Communications exchanged between multiple organizations, e.g., between business trading partners , collaborators, affiliates or a business and its customers.

Interest Groups

In IEEE parlance, Interest groups are the first step in the creation of a standard. For an example, see WPAN.

Interexchange Carrier

IXC. At one stage an IXC was a telephone company that was allowed to provide long-distance telephone service between LATAs but not within any one LATA. Then some states in the United States started allowing intra-LATA competition. Now an IXC is best defined as a telephone company that is allowed to provide long- distance telephone service between LATAs. See IXC and LATA. Contrast with LEC.

Interexchange Channel

IXC. A communications channel or path between two or more telephone exchanges.

Interexchange Customer Service Center

ICSC. The Telephone Company's primary point of contact for handling the service needs of all long distance carriers .

Interexchange Plant

The facilities between one switching center and another switching center; sometimes including line-to-line, no-user-switching centers called "tandem exchanges."

Interface

1. A mechanical or electrical link connecting two or more pieces of equipment together.

2. A shared boundary. A physical point of demarcation between two devices where the electrical signals, connectors, timing and handshaking are defined. The procedures, codes and protocols that enable two entities to interact for a meaningful exchange of information.

3. To bring two things or people together to allow them to talk.

4. A poorly-defined word often used when the speaker is incapable of figuring precisely what he means. No one would ever invite a pretty girl out to lunch asking her to "inter- face" with you. See also Interface Device.

5. According to Steven Johnson's book, "Interface Culture ” How new technology transforms the way we create and communicate," the word interface "refers to software that shapes the interaction between user and computer: The interface serves as a kind of translator, mediating between the two parties, making one sensible to the other. In other words, the relationship governed by the interface is a semantic one, characterized by meaning and expression rather than physical force."

Interface Device

A device which meets a standard electrical interface on one side and meets some other nonstandard interface on the other. The purpose of the device is to allow a device with a nonstandard interface to connect to a device with a standard interface. See also Interface.

Interface Functionality

The characteristic of interfaces that allows them to support transmission, switching, and signaling functions identical to those used in the enhanced services provided by the carrier. As part of its comparably efficient interconnection (CEI) offering, the carrier must make available standardized hardware and software interfaces that are able to support transmission, switching, and signaling functions identical to those used in the enhanced services provided by the carrier.

Interface IC

Interface ICs (integrated circuits) refer to busses and switches that connect and exchange data between different devices according to standards set by various industry standard bodies such as Telecommunications Industry Association or Institute of Electrical and Electronics Engineers (IEEE). Computer circuits use interface standards to move data around - made up of a driver and receiver. The driver sends out the data. the receiver receives the data. For example Maxim invented the RS232 standard which Interface ICs connect and exchange data between different devices based on industry standards

Interface Manager

The original name for Microsoft's Windows. Later called Windows, and finally shipped in its first version in November 1985.

Interface Message Processor

IMP. A processor-controlled switch used in packet-switched networks to route packets to their proper destination.

Interface Nodes

Network nodes used to move data on and off the network.

Interface Overhead

the interface overhead is the remaining portion of the bit stream after deducting the information payload. The interface overhead may be essential (e.g. framing for an interface shared by users) or ancillary (e.g. performance monitoring).

Interface Payload

The portion of the bit stream which can be used for telecommunications services. Any signaling is included in the interface payload. See also Interface Overhead.

Interface Shelves

Shelves in a Rolm PBX cabinet containing the printed circuit card groups that connect telephones, terminals, lines and trunks to CBX interface channels. These shelves also contain shared electronics cards.

Interference

Electromagnetic energy (i.e., electricity, radio, and light) are what we use for transmission purposes in telecommunications and data communications networks. Electromagnetic energy travels in waves, and each transmitted signal is defined as operating at a given frequency, which we call a wavelength in the optical (i.e., light) world, or range of frequencies. If another signal from another source creates a wave front that exactly overlaps your signal in phase (i.e., matches the rise and fall of the wave form), the amplitude (i.e., magnitude, or power level) of the combined signal increases . If another signal from another source creates a wave front that is exactly out of phase, they cancel each other out.

Here's a simpler explanation: Energy you receive with a signal. You don't want the energy. You want the signal. Getting rid of the interference may be a pain. The interference may be man made (e.g., electrical motors, fluorescent light boxes, or radio transmitters) or it may be GOD made (e.g., lightning, sunspots, or static electricity). Some conducted transmission media (fancy term for cabling) are more immune to interference than others. Commonly used wired transmission media, in order of immunity to interference, are:

1. Optical fiber

2. Coax

3. Shielded twisted pair

4. Unshielded twisted pair

5. Unshielded untwisted pair.

Interference Emission

Emission that results in an electrical signal being propagated into and interfering with the proper operation of electrical or electronic equipment. The frequency range of such interference may be taken to include the entire electromagnetic spectrum.

Interferometer

An instrument that employs the interference of light waves for measurement.

Interflow

The ability to establish a connection to a second ACD and overflow a call from one ACD to the other. This provides a greater level of service to the caller.

Interframe

See Interframe Coding.

Interframe Coding

A video term. It's a technique to cut down the size of the video to save on transmission costs. It's a way of source coding where the temporal correlation of moving pictures is used for data reduction. Interframe coding use compression techniques which track the differences between frames of video and eliminates redundant information between frames. Interframe coding stores only once those pixels that don't change. Then multiple frames access those pixels during decompression . This results in more compression over a range of frames than intraframe coding, which compresses information within a single frame.

Interframe Encoding

A way of video compression that transmits only changed information between successive frames. This saves bandwidth. See interframe coding.

Interframe Gap

IFG. The minimum idle time between the end of one frame transmission and the beginning of another. On Ethernet 802.3 LANs the minimum interframe gap is 9.6 micro-seconds.

Interim Interswitch Signal Protocol

A call routing scheme used in STM networks. Formerly known as PNNI Phase 0. IISP is an interim technology meant to be used pending completion of PNNI Phase 1. IISP uses static routing tables established by the network administrator to route connections around link failures.

Interim Local Number Portability

See LNP and Number Portability.

Interim Number Portability

See LNP and Number Portability.

Interim Operating Authority

IOA. Authority granted by the FCC for a company to operate a cellular system during the interim between that company's application for a cellular license and the FCC's granting of such a license. IOAs usually apply in situations where litigation (i.e., lawsuits) threatens to extend the hearings and licensing process for long periods of time. They also sometimes are granted when license requests are unop- posed, as the normal licensing process can take many months, and fast-developing or transient needs of the cellular community might be otherwise left unsatisfied. See also STA.

Interior

An ATM term. Denotes that an item (e.g., link, node, or reachable address) is inside of a PNNI routing domain.

Interlace

In TV, each video frame is divided into two fields with one field composed of the odd- numbered horizontal scan lines and the other composed of the even-numbered horizontal scan lines. Each field is displayed on an alternating basis. This is called interlacing. It is done to avoid flicker. See also Interlacing.

Interlaced GIF

When you're downloading a Web page, which contains images, interlaced GIF images appear first with poor resolution and then improve in resolution until the entire image has arrived, as opposed to arriving linearly from the top row to the bottom row. This lets users get a quick idea of what the entire image will look like while waiting for the rest to load. Your Web browser has to support progressive display. Non-progressive-display Web browsers will still display interlaced GIFs, but only after they have arrived in their entirety.

Interlaced Image

A Web term. A GIF image that is displayed full- sized at low resolution while it is being loaded, and at increasingly higher resolutions until it is fully loaded and has a normal appearance. See Interlaced GIFs.

Interlaced Scanning Mode

A scheme that takes two passes to paint an on screen image, painting every other line on the first pass and sequentially filling in the rest of the lines on the second pass. This scheme usually causes flicker.

Interlacing

Regular TV signals are interlaced. In the US there are 525 scanning lines on the regular TV screen. This is the NTSC standard. Interlaced means the signal refreshes every second line 60 times a second and then jumps to the top and refreshes the other set of lines also 60 times a second. Non-interlaced signals, which are used in the computer industry, means each line on the entire screen is refreshed X times. X times depends on what the video card is outputting to the color monitor. The more expensive the card and the monitor, the more often the monitor will be refreshed. The more it's refreshed, the better and more stable it looks ” the less perceived flicker. For example, text on an NTSC United States TV set tends to "flicker." It doesn't on a non-interlaced monitor. Typical non- interlaced computer monitors refresh at 60 to 72 times a second. But good ones refresh at higher rates. Generally, anything over 70 Hz (i.e. 70 times a second) is considered to be flicker-free and therefore preferred, if you can afford it. In short, buy an non-interlaced monitor. You'll like it better.

InterLATA

Services, traffic or facilities that originate in one LATA, crossing over and terminating in another Local Access and Transport Area. (LATA). This can be either Interstate or Intrastate service, traffic or facilities. Under provisions of Divestiture, the Bell operating companies cannot provide Inter-LATA service, but can provide Intra-LATA service. Some LATAs are very large. So some "local" phone companies provide the equivalent of long distance service. And some of these phone companies have different pricing packages. Some of these packages are cheap, but not highly-publicized. See also InterLATA Service and LATA.

InterLATA Call

A call that is placed within one LATA (Local Access Transport Area) and received in a different LATA. These calls are currently carried by a long distance company.

InterLATA Carrier

IC. Any carrier that provides telecommunications services between a point in a LATA and a point in another LATA or outside a LATA.

InterLATA Competition

Originally long distance telephone companies in the United States were not allowed to provide InterLATA telecom services. Later, many Public Utility Commissions (PUC) in ARF (Alternative Regulatory Framework) Phase III started to consider it. And many state agencies started to allow long distance phone companies to compete with local monopolies to carry intraLATA toll calls.

InterLATA Service

As defined by the Telecommunciations Act of 1996, the term 'interLATA service' means telecommunications between a point located in a local access and transport area and a point located outside such area.

Local access and transport area: The term 'local access and transport area' or 'LATA' means a contiguous geographic area ”

1. established before the date of enactment of the Telecommunications Act of 1996 by a Bell operating company such that no exchange area includes points within more than 1 metropolitan statistical area, consolidated metropolitan statistical area, or State, except as expressly permitted under the AT&T Consent Decree; or

2. established or modified by a Bell operating company after such date of enactment and approved by the Commission.

Interleave

1. The transmission of pulses from two or more digital sources in time- division sequence over a single path.

2. A data communication technique, used in conjunction with error-correcting codes, to reduce the number of undetected error bursts. In the interleaving process, code symbols are reordered before transmission in such a manner that any two successive code symbols are separated by I-1 symbols in the transmitted sequence, where I is called the degree of interleaving. Upon reception, the interleaved code symbols are reordered into their original sequence, thus effectively spreading or randomizing the errors (in time) to enable more complete correction by a random error-correcting code.

3. Interleaving also refers to the way a computer writes to and reads from a hard disk. Understanding interleaving is critical if you want to get your hard disk to work at its maximum speed (without in any way damaging the disk). Let's look at the way MS-DOS reads information from a hard disk. All hard disks are controlled by a special card called a hard disk controller card. Let's say your computer wants a file. It tells the hard disk controller card it wants the file. The controller searches the disk for the first sector of the requested file, reads that sector (usually 512 bytes) to your computer's RAM and then transfers the information to the CPU to be processed. When this is complete, the controller goes back to the hard disk and searches for the file's second sector. The process continues in this way until the file is completely read.

The problem is that while the controller and the CPU are doing their things, the hard disk itself is spinning 3,600 times a minute. By the time the controller reads one sector and it is ready to return to the disk, the next consecutive file sector has spun past the read/write head. If the file is stored in contiguous sectors, the controller must wait for the disk to complete its revolution before it can read the next file sector. To solve this problem, hard drive makers developed a concept called interleave setting, which tells the hard drive controller to skip a certain number of sectors when it writes a file to disk. Thus, when the file is later read back, the appropriate file sectors should fall under the read/write heads at the appropriate time.

If the controller reads or writes one sector and then skips a sector, the interleave is 2 (every other sector is used to store logically consecutive blocks). The interleave is sometimes written as 2:1. If the controller writes to one sector and then skips two, the interleave is 3 or 3:1. The interleave factor is usually established by the manufacturer or reseller of the hard disk/controller combination. If someone else assembles the hard disk/controller combination, that person may need to experiment to determine the correct interleave factor ” i.e. the one that works fastest without messing up.

Setting the "correct" interleave settings on your hard disk is critical to getting maximum performance out of your hard disk. Here's a test that a writer for PC Resource Magazine did. He copied the same files from one part of his hard disk to another part using different interleave settings:

Setting	Time to copy file
3	1 min 15 seconds
4	1 min 17 seconds
5	1 min 1 second
6	35 seconds
7	41 seconds
8	1 min 10 seconds

Clearly his best interleave setting is six. There are two ways of choosing the correct interleave setting. You can do it by trial and error as the writer did. His test took three hours. Or buy a program and do it in seconds. The best program is called Disk Technician. It's from a company called Prime Solutions in San Diego. Sadly, the program doesn't work on certain laptops and on certain controller card/hard disk combinations.

Interleaved Memory

An option on some system boards that increases processing speed by assigning memory locations on an alternating basis to two banks of RAM. The computer has to wait one cycle between accesses to a single bank of memory, but it can access a different bank without having to wait.

Intermediate Assist

A method for pulling cables into conduits or duct liners in which manual labor or machines are used to assist the pulling at intermediate manholes.

Intermediate Cross-Connect

an interconnect point within backbone wiring. for example, the interconnection between the main cross-connect and telecommunications closet or between the building entrance facility and the main cross-connect.

Intermediate Distribution Frame

IDF. A metal rack designed to connect cables and located in an equipment room or closet. Consists of bits and pieces that provide the connection between inter-building cabling and the intra-building cabling, i.e. between the Main Distribution Frame (MDF) and individual phone wiring. There's usually a permanent big, fat cable running between the MDF and IDF. The changes in wiring are done at the IDF. This saves confusion in wiring. See also Feeder Cable and Connecting Block.

Intermediate Frequency

IF. A microwave frequency that has been reduced from its native frequency, so that it can be processed. This is necessary because a microwave cannot be fully processed in its native frequency.

Intermediate Frequency Transformer

A transformer designed to amplify the intermediate frequencies generated in a superheterodyne radio receiver. These are normally sharply tuned to a single frequency band .

Intermediate High-Usage Trunk Group

A Bellcore definition. A high- usage trunk group that receives route-advanced overflow traffic and may receive first-route traffic and/or switched-overflow traffic.

Intermediate Reach

Intermediate reach refers to optical sections from a few kilometers (km) to approximately 15 km. An AT&T SONET term.

Intermediate System

An OSI term which refers to a system that originates and terminates traffic, as well as forwarding traffic to other systems.

Intermittent Problems

Intermittent problems are issues or bugs that come to light only after systems have been running for some time, or certain infrequently performed sequences of events are performed. Often many thousands of calls need to be put through before they are discovered . And bugs may only be seen occasionally, perhaps one of every 100 times something is done. Intermittent problems are among the hardest to find and duplicate.

Intermix

A mode of service defined by Fibre Channel that reserves the full Fibre Channel bandwidth for a dedicated (Class 1) connection, but also allows connectionless (Class 2) traffic to share the link if the bandwidth is available.

Intermodulation

IM. The production, in a nonlinear element of a system, of frequencies corresponding to the sum and difference frequencies of the fundamentals and integral multiples (harmonics) of the component frequencies that are transmitted through the element.

Intermodulation Distortion

IMD. Nonlinear distortion characterized by the appearance of frequencies in the output, equal to the sum and difference frequencies of integral multiples (harmonics) of the component frequencies present in the input. Harmonic components also present in the output are usually not included as part of the intermodulation distortion.

Internal Bus

See Local Bus.

Internal F-ES

A cellular radio term. A fixed End System within the administrative domain of the CDPD service provider. Typically provides value-added support services such as network management, accounting, directory, and authentication services.

Internal Modem

A modem on a printed circuit card which is inserted into one of the slots on a PC (personal computer). The other type of modem for a PC is an external modem ” essentially a modem with the same circuitry as an internal modem but with a metal or plastic case. An internal modem costs slightly less than an external one. Internal modems are good if you're short of desk space and afraid your external modem will be stolen. External modems have lights so it's easier to tell what's going on. Everybody has their theories on which type of modem is best. We prefer the external ones ” largely for their lights and ease of moving around.

Internal Reachable Address

An ATM term. An address of a destination that is directly attached to the logical node advertising the address.

Internal Reflection

As light rays enter a fiber optic link at an angle, they hit a barrier known as the cladding/core barrier . If the angle is less than a certain "critical angle" all of those rays are reflected back into the core of the fiber and continue propagating through the fiber to the end of the link. See Index of Refraction.

Internal Switch Interface System

ISIS7. The operating system used in Concert Packet Services Engines to schedule the node's tasks , allocate hardware resources among users, transfer information between devices, and run software programs.

International 800 Service

You can now have your customers overseas call you for free on an 800 line, just as your domestic customers do. The service is available from countries including Australia, Brazil, France, Hong Kong, Israel, Italy, Japan, Sweden, Switzerland and the United Kingdom. Overseas 800 service is often known as "Freephone."

International Ad Hoc Committee

IAHC. One of the organizations which parcels out Internet domain names. The IAHC has proposed to add a number of TLD (Top Level Domain) names to the existing list of .com (commercial), .edu (education), .gov (government), .mil (military) and .org (not-for-profit organizations). Those proposed TLDs include .firm (businesses), .store (stores), .web (entities emphasizing cultural and entertainment activities), .rec (entities emphasizing recreation/entertainment activities), . info (entities providing information services) and .nom (those wishing individual or personal nomenclature ). See Domain, Domain Name Server, and Domain Naming Service.

International Alphabet No. 5

IA5. Internationally standardized alphanumeric code with national options. ASCII is United States version.

International Ampere

The current which will in one second deposit 0.001118 gram of silver from a neutral solution of silver nitrate.

International Atomic Time

inTernational Atomic tIme (TAI) is measured in the SI second, defined in terms of vibrations of a cesium atom. It is therefore not explicitly tied to the Earth's rotation, although that was of course the motivation for the original definition of the second. An SI second is a unit of time equal to 1/60 of a minute or 1/3600 of an hour . The international definition was originally 1/86400th of a mean solar day in 1900, but is now instead the time required for 9,192,631,770 vibrations of a Cesium atom.

International Callback

Calling the United States from many countries abroad is far more expensive than calling those countries from the United States. A new business called International Callback has started. It works like this. You're overseas. You dial a number in the United States. You let it ring once. It won't answer. You hang up. You wait a few seconds. The number you dialed in the U.S. knows it was you calling. There is a piece of equipment on that number that "hears" it ring and knows it's you since no one else has that number. (Typically it's done with Centrex service.) That was your special signal that you want to make a call. A switch attached to that line then calls you instantly. When you answer (overseas, obviously) it conferences you with another phone line in the United States and gives you U.S. dial tone. You can then touchtone from overseas your American number, just as if you would, were you physically in the U.S. There are huge savings. U.S. international callback operators can offer as high as 50% savings on calls from South America, where international calling rates are very high. The process of international callback is being automated with software and dialing devices. International callback is also helping to bring down the high cost of calling the U.S. from overseas. In recent years , deregulation has caused the price of international calls in many countries to fall dramatically. And now international callback or just callback is being done from other countries, including and especially Israel. A company called Kallback in Seattle, WA. has received a service mark from the U.S. Patent and Trademark Office for the words "callback" and "kall- back" and sends letters to and threatens law suits against companies who use "their" words. See Callback.

International Carrier

A carrier that generally provides connections between a customer located in World Zone 1 and a customer located outside of World Zone 1, but with option of providing service to World Zone 1 points in North American Numbering Plan area codes outside the U.S.

International Center For Information Technologies

A Washington "think tank" whose mission is to bring together discussion on new telecommunications and computer technologies. Targeted at senior executives who are looking for ways to apply new technologies to gaining competitive edges for their company.

International Computer Security Association

See ICSA.

International Denial

An optional restriction on your cellular phone that prevents the cellular number from marketing international calls. Some carriers place this restriction on all subscribers using their service.

International Direct Distance Dialing

IDDD. Being able to automatically dial international long distance calls from your own phone. The direct calling by the originating customer to the distant (international) called customer via automatic switching. IDDD is synonymous with the phrases international direct dialing and international subscriber dialing.

International Engineering Consortium

The International Engineering Consortium, established in 1944, is a non-profit organization dedicated to catalyzing positive change in the information industry and its university communities. The Consortium provides educational opportunities for today's information industry professionals and conducts a variety of industry-university programs. The IEC also conducts research and provides publications addressing major opportunities and challenges of the information age. More than 70 leading, high technology universities are currently affiliated with the Consortium. [e-mail].

International Freephone Service

IFS. The ITU-T term for international toll-free service. IFS works on the basis of Universal International Freephone Numbers (UIFNs). A UIFN consists of a dialing pattern comprising an international prefix (e.g., 011), a three-digit country code (e.g., 800) for global service application, and an 8-digit Global Subscriber Number (GSN). See UIFN for much more detail.

International Calling Codes
Albania	355
Algeria	213
American Samoa	684
Andorra	376
Angola	244
Anguilla	264
Antarctica	672
Antigua and Barbuda	1
Argentina	54
Armenia	374
Aruba	297
Australia	61
Austria	43
Azerbaijan	994
Bahamas	1
Bahrain	973
Bangladesh	880
Barbados	1
Belarus	375
Belgium	32
Belize	501
Benin	229
Bermuda	1
Bhutan	975
Bolivia	591
Bosnia and Herzegovina	387
Botswana	267
Brazil	55
Brunei Darussalam	673
Bulgaria	359
Burkina Faso	226
Burundi	257
Cambodia	855
Cameroon	237
Canada	1
Cape Verde	238
Cayman Islands	1
Central African Republic	236
Chad	235
Chile	56
China	86
Christmas Island	672
Cocos (Keeling) Islands	672
Colombia	57
Comoros	269
Congo	242
Cook Islands	682
Costa Rica	506
Cote D'Ivoire (Ivory Coast)	225
Croatia (Hrvatska)	385
Cuba	53
Cyprus	357
Czech Republic	420
Czechoslovakia (former)	420
Denmark	45
Diego Garcia	246
Djibouti	253
Dominica	1
Dominican Republic	1
Ecuador	593
Egypt	20
El Salvador	503
Equatorial Guinea	240
Eritrea	291
Estonia	372
Ethiopia	251
Falkland Islands (Malvinas)	500
Faroe Islands	298
Fiji	679
Finland	358
France	33
French Antilles	596
France, Metropolitan	33
French Guiana	594
French Polynesia	689
Gabon	241
Gambia	220
Georgia	995
Germany	49
Ghana	233
Gibraltar	350
Great Britain (UK)	44
Greece	30
Greenland	299
Grenada	1
Guadeloupe	590
Guam	671
Guatemala	502
Guinea	224
Guinea-Bissau	245
Guyana	592
Haiti	509
Heard and McDonald Islands	692
Herzegovina	387
Honduras	504
Hong Kong	852
Hungary	36
Iceland	354
India	91
Inmarsat
East Atlantic Ocean	871
Indian Ocean	873
Pacific Ocean	872
West Atlantic Ocean	874
Indonesia	62
Iran	98
Iraq	964
Ireland	353
Israel	972
Italy	39
Ivory Coast	225
Jamaica	1
Japan	81
Jordan	962
Kazakhstan	7
Kenya	254
Kiribati	686
Korea North	850
Korea South	82
Kuwait	965
Kyrgyzstan	7
Laos	856
Latvia	371
Lebanon	961
Lesotho	266
Liberia	231
Libya	218
Liechtenstein	41
Lithuania	370
Luxembourg	352
Macau	853
Macedonia	389
Madagascar	261
Malawi	265
Malaysia	60
Maldives	960
Mali	223
Malta	356
Mariana Islands	670
Marshall Islands	692
Martinique	596
Mauritania	222
Mauritius	230
Mayotte	269
Mexico	52
Micronesia	691
Moldova	373
Monaco	377
Mongolia	976
Montserrat	1
Morocco	212
Mozambique	258
Myanmar	95
Namibia	264
Nauru	674
Nepal	977
Netherlands	31
Netherlands Antilles	599
New Caledonia	687
New Zealand	64
Nicaragua	505
Niger	227
Nigeria	234
Niue	683
Norfolk Island	672
Northern Mariana Islands	670
Norway	47
Oman	968
Pakistan	92
Palau	680
Panama	507
Papua New Guinea	675
Paraguay	595
Peru	51
Philippines	63
Pitcairn	872
Poland	48
Portugal	351
Puerto Rico	1
Qatar	974
Republika Srpska	387
Reunion Island	262
Romania	40
Russian Federation	7
Rwanda	250
Saint Kitts and Nevis	1
Saint Lucia	1
Saint Vincent & the Grenadines	1
Samoa	685
San Marino	378
Sao Tome and Principe	239
Saudi Arabia	966
Senegal	221
Seychelles	248
Sierra Leone	232
Singapore	65
Slovak Republic	421
Slovenia	386
Solomon Islands	677
Somalia	252
South Africa	27
Spain	34
Sri Lanka	94
St. Helena	290
St. Pierre and Miquelon	508
Sudan	249
Suriname	597
Svalbard and Jan	378
Mayen Islands Swaziland	268
Sweden	46
Switzerland	41
Syria	963
Taiwan	886
Tajikistan	7
Tanzania	255
Thailand	66
Togo	228
Tokelau	690
Tonga	676
Trinidad and Tobago	1
Tunisia	216
Turkey	90
Turkmenistan	993
Turks and Caicos Islands	649
Tuvalu	688
US Minor Outlying Islands	1
USSR (former)	7
Uganda	256
Ukraine	380
United Arab Emirates	971
United Kingdom	44
United States	1
Uruguay	598
Uzbekistan	7
Vanuatu	678
Vatican City State	396
Venezuela	58
Viet Nam	84
Virgin Islands (British)	1
Virgin Islands (U.S.)	1
Wallis and Futuna Islands	681
Western Sahara	34
Western Samoa	689
Yemen	967
Yugoslavia	381
Zaire	243
Zambia	260
Zimbabwe	263

International Gateways

The switches in the various domestic long distance networks (e.g. MCI, AT&T and Sprint) which interface their networks with International telecommunications networks. All US International calls are routed through an international gateway.

International Morse Code

See Morse Code.

International Organization For Standardization

ISO. An organization established to create standards. See ISO.

International Prefix

The combination of customer-dialed digits prior to dialing of the country code required to access the automatic outgoing international equipment in the originating country.

International Radiocommunications Advisory Committee See

IRAC.

International Record Carrier

IRC. One of a group of carriers that, until recently, was part of a monopoly of U.S. common carriers certified to carry data and text to locations outside the U.S. In recent years, regulation of this type of service has been markedly relaxed . Most of the IRCs got bought by MCI.

International Private Line Circuits

IPLC. The circuit lines used to connect nodes on the network. See also Trunk Circuit.

International Shortwave Broadcast Station

A station that sends programs overseas either for direct reception by listeners abroad or for intermediate reception by overseas relay stations that rebroadcast the programs on shortwave or medium wave stations to nearby audiences.

International Standards Organization

ISO. See ISO.

International Switching Carrier

ISC. An exchange whose function is to switch telecommunications traffic between national network and the networks of other countries. Also known as an international gateway office.

International Telecommunications Organization

ITO. Foreign government agencies responsible for regulating communications. Formerly known as Postal Telephone and Telegraph (PTT).

International Telecommunications Union

ITU. Anglicization of the proper French name of the Union Internationale des Telecommunications (UIT), resident in Geneva, Switzerland. ITU is the for agreements on telecommunications technical and operating standards and is a constituent body of the United Nations, engaging also in international development and education concerning telecommunications. ITU. Its most successful work is done in the establishment (but not enforcement of) standards and the allocation of radio frequencies worldwide ” including satellites , etc. For a much bigger explanation, see ITU and ITU-T.

International Telecommunications Union-Radiocommunication Sector ITU-R

Formerly the International Radio Consultative Committee (CCIR). The technical study branch of the International Telecommunication Union responsible for the study of technical and operating questions relating specifically to radio communications. See also ITU-T.

International Telegraph Alphabet #1

ITA 1. World-standard CCITT version of the manual telegrapher's code. Colloquial name: International Morse Code.

International Telegraph Alphabet #2

ITA 2. World-standard CCITT version of the 5-unit (also called 7.5 unit) teleprinter code used for Telex, international telegrams and most general telegraphy by wire lines; Colloquial name: Baudot code.

International Telegraph Alphabet #3

ITA 3. World-standard CCITT version of a 6-unit extended set of ITA 2 to include characters needed for automatic type- setting directly from telegraph circuits. Colloquial names: Teletypesetter code, press code, extended Baudot code, and others.

International Telegraph Alphabet #4

ITA 4. World-standard CCITT version of a 7-unit code in which only the combinations using 4 marking bits are valid; receiving any character with more or less than 4 marking bits is its error checking feature. Colloquial names: 7-unit ARQ Code, Moore ARQ Code, Moore Code, RCA Code, and others.

International Telegraph Alphabet #5

ITA 5. World-standard CCITT version of a 7-unit teleprinter code with an 8th parity bit also used for asynchronous data terminals such as minicomputers or PCs. Colloquial name: ASCII code.

International Telephone Address

A four-part code specifying a unique address for any telephone company in the world.

International Toll Free Service

See IFTS.

International Wireless Telecommunications Association

See IWTA.

Internesia

The tendency to find wonderful things on the Internet and then forget where they were.

Internet

It is very hard to define the Internet in a way that is either meaningful nor easy to grasp. To say the Internet is the world's largest and most complex computer and communications network is to trivialize it. But it is. To say it's the computer network for everybody in the world is to trivialize it. But it is. To say that it is fast becoming the world's global shopping mall (for buying and selling) is to trivialize it. To say that it's becoming the network for the world's corporations to communicate is to trivialize it. But it is. To say that it's replacing both physical mail and electronic faxes is to trivialize it. But it is. It is clearly the most important happening in the computing, communications and telecommunications industries since the invention of the computer or the transistor . The Internet is both a transport network ” moving every form of data around the world (voice, video, data and images) ” and a network of computers which allow you (and them) to access, retrieve, process and store all manner of information. No one really has a clear idea of the Internet's size, its growth or its capacity. We know that it grows daily. The most important part of the Internet for all of us normal people is something called the World Wide Web, as characterized by all those web sites starting with www. The World Wide Web is a subset of the Internet. Web Wid Web sites sit on computers worldwide joined by telecommunications links. Each web site has documents conforming to a specific Internet protocol called HTTP, which stands for HyperText Transfer Protocol. HTTP is the standard way of transferring information across the Internet and the World Wide Web. The reason we can read all the documents on all the Web sites is that the pages are written in HTML or Hypertext Markup Language, which tells your Web browser (e.g. Internet Explorer or Netscape) how to display the page and its elements (photos, videos , music, etc.) The defining feature of the Web is its ability to connect pages to one another ” as well as to audio, video, and image files ” with hyperlinks . Just click a link, and suddenly you're at a Web site on the other side of the world. How does the Internet find my web site www.InSearchOfThePerfectInvestment.com? Any computer attached at that moment to the Internet has an address ” just like a phone number, except that it's typically a 16- digit address. When you type in www.InSearchOfThePerfectInvestment.com, your browser sends a command out to a database on the Internet in effect asking, "What is www.InSearchOfThePerfectInvestment.com?" Back comes the answer that it's 64.226.86.128. Your browser connects you and there you. An IP address on the web is a 4- to 12-digit number. The digits are organized in four groups of numbers (which can range from 0 to 255) separated by periods. If your computer is a web site permanently attached to the Internet, it will have a permanent address, i.e. it will always be the same. When you connect your personal computer to the Internet, your ISP (Internet Service Provider) will likely assign you a new address every time you connect. For a full explanation, see DHCP.

The first question everyone asks is, "Who runs the Internet." The simple answer is "everyone and no one." Think of the Internet as two parts . The first are technical standards ” how everyone connects to the Internet. These standards are set by various committee under the direction of something called the IETF. The second are the communications circuits which carry the Internet's traffic. There are hundreds of companies ” including basically every traditional local and long distance phone company in the world ” that interconnect. How they get paid and pay each other other depends on arrangements they have amongst themselves .

The Internet's roots are in a U.S. Defense Department network called Advanced Research Project Agency NETwork (ARPAnet), established in 1969. ARPAnet tied universities and research and development organizations to their military customers, and provided connectivity to a small number of supercomputer centers to support timesharing applications. Quickly, the biggest application among its users became email. Much of the funding was provided by NSFNET (National Science Foundation NETwork). In the mid-1990s, the Internet was "commercialized", extending its use to anyone with a PC, a modem, a telephone line and an access provider ” a special company known as an Internet Service Provider or Internet Access Provider. The Internet has become a major new publishing, research and commerce medium. I believe that its invention is as important to the dissemination of knowledge, to peoples' life styles and to the way we'll be conducting business in coming years as the invention of the Gutenberg Press was in 1453.

At its heart, the Internet is many large computer networks joined together over high- speed backbone data links ranging from 56 Kbps (now rare) to T-1, T-3, OC-1, OC-3 and higher. The Internet now reaches worldwide. Depending on the whim of the local government (which typically controls the local phone company and thus access to the Internet for its citizenry) you can pretty well get onto the Internet and roam it unchecked. The governments of Singapore, the People's Republic of China, Burma, Saudi Arabia and a few others limit their peoples' access to the Internet. The topology of the Internet and its subnetworks changes daily, as do its providers and its content. The bottom line is that the makeup of the Internet ” i.e. how it works ” is not all that important. It is the applications and information available on it that are important ” the most significant of which are e- mail (electronic mail) and the World Wide Web. Commercial networks from AT&T, SPRINT, Worldcom and many others now carry the bulk of the traffic. As NSFNET (i.e. the U.S. Government) no longer funds the Internet, it has been commercialized, with money changing hands in complex ways between users, companies with Web sites, Internet Access Providers, long distance providers, government, universities and others. Increasingly, businesses are joining their computers to the Internet. There are now over 125 million Internet sites you can visit, running on over 75 million computers. There are probably 500 million computers worldwide equipped to reach the Internet ” from the laptop I'm writing this on, to the desktop at your office.

The Internet's networking technology is very smart. Every time someone hooks a new computer to the Internet, the Internet adopts that hookup as its own and begins to route Internet traffic over that hookup and through that new computer. Thus as more computers are hooked to the Internet, its network (and its value) grows exponentially. The Internet is basically a packet switched network based on a family of protocols called TCP/IP, which stands for Transmission Control Protocol/Internet Protocol (TCP/IP), a family of networking protocols providing communication across interconnected networks, between computers with diverse hardware architectures and between various computer operating systems. Most PCs, including Windows-based machines and Macintoshes, will happily communicate using TCP/IP.

How TCP Works: TCP is a reliable, connection-oriented protocol. Connection-oriented implies that TCP first establishes a connection between the two computer systems that intend to exchange data (e.g. your PC and the host computer you're trying to reach, which may be thousands of miles away). Since most networks are built on shared media (for example, several systems sharing the same cabling), it is necessary to break chunks of data into manageable pieces so that no two communicating computers monopolize the network. These pieces are called packets. When an application sends a message to TCP for transmission, TCP breaks the message into packets, sized appropriately for the network, and sends them over the network. Because a single message is often broken into many packets, TCP marks these packets with sequence numbers before sending them. The sequence numbers allow the receiving system to properly reassemble the packets into the original original order, i.e. the original message. TCP checks for errors. And finally, TCP uses port IDs to specify which application running on the system is sending or receiving the data. The port ID, checksum, and sequence number are inserted into the TCP packet in a special section called the header. The header is at the beginning of the packet containing this and other "control" information for TCP.

How IP Works: IP is the messenger protocol of TCP/IP. The IP protocol, much simpler than TCP, basically addresses and sends packets. IP relies on three pieces of information, which you provide, to receive and deliver packets successfully: IP address, subnet mask, and default gateway. The IP address identifies your system on the TCP/IP network. IP addresses are 32-bit addresses that are globally unique on a network. There's much more on TCP/IP in my definition on TCP/IP and on Internet Addresses in that definition.

Here's how the Internet is used: As a computer network joining two (or more) computers together in a session, it is basically transparent to what it carries. It doesn't care if it carries electronic mail, research material, shopping requests, video, images, voice phone calls, requests for information, faxes ... or anything that can be digitized, placed in a packet of information and sent. A packet-switched network like the Internet injects short delays into its communications as it disassembles and assembles the packets of information it sends. And while these short delays are not a problem for non-real time communications, like email, they present a problem for "real-time" information such as voice and video. The Internet can inject a delay of as much as half a second between speaking and being heard at the other end. This makes conversation difficult. Internet telephony, as it's called when it runs on the Internet, is getting better, however, as the Internet improves and voice coding and compression techniques improve. I've enjoyed some relatively decent conversations to distant places.

Probably the most famous quote about the Internet is one from John Doerr, one of Silicon Valley's most famous venture capitalists. He said, "The Internet is the greatest legal creation of wealth in the history of the planet." Later, after the dot com bust he came to regret his words. By hyping wealth rather than invention, he has confessed, he distracted the industry from pursuing revolutionary technologies.

Now for a little history on the Internet. In the early 1990s the Internet was run by and for the United States government. There was no public use of the Internet. There were no commercial applications. In fact it wasn't even clear to the Federal Government what the Internet actually was. So an organization called the Federal Networking Council (FNC), which actually managed networking for the Federal Government, on October 24, 1995, unanimously passed a resolution defining the term Internet. This definition was developed in consultation with the leadership of the Internet and Intellectual Property Rights (IPR) Communities. RESOLUTION:

"The Federal Networking Council (FNC) agrees that the following language reflects our definition of the term "Internet". "Internet" refers to the global information system that ”

1. is logically linked together by a globally unique address space based on the Internet Protocol (IP) or its subsequent extensions/follow-ons;

2. is able to support communications using the Transmission Control Protocol/Internet Protocol (TCP/IP) suite or its subsequent extensions/follow-ons, and/or other IP-compatible protocols; and

3. provides, uses or makes accessible, either publicly or privately, high level services layered on the communications and related infrastructure described herein."

MCI Mail was the first commercial application attached to the Internet. Once it got one, all the other email services wanted on...and the rest is history. See various Internet definitions following. See also Berners-Lee, Domain, Domain Naming System, Grid Computing, gTLD, ICANN, Internet2, Internet Appliance, Internet Protocol, Internet Telephony, Intranet, IP Telephony, Surf, TCP/IP, Web Browser and Web Services.

Internet Access

The method by which users connect to the Internet, usually through the service of an Internet Service Provider (ISP).

Internet Access Provider

See IAP. Internet Address

When you travel the Internet or its World Wide Web area, you need an address to get to where you want to go ” just like you need an address on a letter you mail or a phone number you wish to reach. All Internet addresses are expressed in dotted decimal notation of four fields of eight bits. In binary code, each bit has two possible values, 0 or 1. Therefore, each 8- bit field yield two to the eighth power, or 256 possible combinations. Since one of the possible combinations is 000, which means nothing, it is not used, thereby leaving 255 possible numbers in each field. IP addresses are written as XXX.XXX.XXX.XXX, where X is any number between 0 and 9, and where each 3-digit field has a value between 001 (i.e., 1) and 256. Internet addresses currently are based on the IPv4 (Internet Protocol version 4 protocol), which uses a 32-bit code in the 20-octet IP header to identify host addresses. A 32-bit address field yields 2 to the 32nd power possible addresses ” that's 4,294,967,296 addresses. that seems like a lot of addresses, but it's not enough in the context of the commercialized Internet. Note that IPv6 has been standardized by the IETF (Internet Engineering Task Force), but has yet to be widely implemented, as equipment upgrades generally are required. Among the advantages of IPv6 is an address field expanded to 128 bits. A 128-bit address field yields 2 to the 128 power addresses ” that's 340,282,366,920,939,463,463,374,607,431,768,211,456 distinct addresses. That's enough for approximately 32 addresses for every square inch of dry land on the Earth's surface, which should be enough for a while. No one wants to remember all those numbers when they go checking out their favorite site. So they came up with a neat idea of naming sites and having a bunch of computers do the translation, very similar to what happens with 800 toll-free numbers in North America. As a result Web URLs (Uniform Resource Locators) and e-mail addresses (such as www.harrynewton.com and harry @harrynewton.com) are textual addresses that are translated into correlating IP addresses through DNSs (Domain Name Servers, i.e. dedicated translation computers), which maintain tables of both domain names and IP addresses. For example, if you wish to reach www.Javanet.com, you can type www.Javanet.com in your browser or you can simply type 209.94.128.8. But www.Javanet.com is easier to remember. Internet addresses are organized into hierarchical "classes," as follows :

Class A Addresses: Begin with a "0" bit. Of a possible 128 Class A networks, only 51 networks exist. Examples include General Electric Company, IBM Corporation, AT&T, Hewlett-Packard Company, Ford Motor Company, and the Defense Information Systems Agency. They all are huge organizations, and require the highest possible categorization.

Class B Addresses: Begin with a "10" bit sequence. Of a possible 65,536 Class B networks, only about 12,000 exist.

Class C Addresses: Begin with a "110" binary bit sequence. Most applicants are assigned Class C addresses in blocks of 255 IP addresses. As of January 1998, about 800,000 Class C addresses were assigned.

Class D Addresses: Begin with a "1110" bit sequence. They are intended for multicast purposes.

Class E Addresses: Begin with a "1111" bit sequence. They are reserved for future use. Now, the term "Internet Address" can be a bit misleading. As we have seen, it actually refers to an "IP Address," unless it's a URL, of course. Even if it's a URL, it's translated into an IP address. IP addresses often are used in the LAN (Local Area Network), as well as in the Internet and other public packet data networks. In such a case, one IP address often is used internal to the LAN domain, and another in the Internet domain, in order to mask the internal IP subnet address from the outside world. Masking the internal IP address essentially "masks," or hides, the true IP address of your workstation from the outside world. You may do this for one simple reason ” you don't want the outside world to be able to get to your PC. The internal IP address might be either IPv4 or IPv6, while the Internet "outside world" address currently is always IPv4. In either event, the IP addresses are translated, one to the other, through a process of NAT (Network Address Translation), which is accomplished in an access router. On the outbound side, your true IP address is translated into an Internet IP address associated with the router. Responses to your transmissions are addressed to the router, which then translates them back into your true IP address for successful delivery. This translation and masking process secures and protects your identity. See NAT for a full explanation of this process. See also Subnet Mask.

Internet Appliance

A sub-$500 machine specially designed for Internet browsing and first proposed in the late Fall of 1995 by Larry Ellison, head of database software company Oracle. Part of its appeal to people outside Microsoft and Intel is that the Internet Appliance would not have to be based on standard PC technology. It need have an Intel chip and need not run Windows. This device is also called an Internet Terminal, a Network Computer or an IPC, an Interpersonal computer. The original description of the Internet Appliance was that it would come with 4mb of RAM, 4mb of flash memory, processor, monitor, keyboard and mouse ” all for under $500.

Internet Architecture Board

The Internet Architecture Board (IAB) is a technical advisory group of the Internet Society. Its responsibilities include:

IESG Selection: The IAB appoints a new IETF chair and all other IESG candidates, from a list provided by the IETF nominating committee.

Architectural Oversight: The IAB provides oversight of the architecture for the protocols and procedures used by the Internet.

Standards Process Oversight and Appeal: The IAB provides oversight of the process used to create Internet Standards. The IAB serves as an appeal board for complaints of improper execution of the standards process.

RFC Series and IANA: The IAB is responsible for editorial management and publication of the Request for Comments (RFC) document series, and for administration of the various Internet assigned numbers.

External Liaison: The IAB acts as representative of the interests of the Internet Society in liaison relationships with other organizations concerned with standards and other technical and organizational issues relevant to the world-wide Internet.

Advice to ISOC: The IAB acts as a source of advice and guidance to the Board of Trustees and Officers of the Internet Society concerning technical, architectural, procedural, and (where appropriate) policy matters pertaining to the Internet and its enabling technologies.

Internet Assigned Numbers Authority

IANA. This group is responsible for the assignment of unique Internet parameters (e.g., TCP port numbers, and ARP hardware types), and managing domain names. It also was responsible for administration and assignment of IP (Internet Protocol) numbers within the geographic areas of North America, South America, the Caribbean and sub-Saharan Africa; on December 22, 1997, that responsibility was shifted to ARIN (American Registry for Internet Numbers). www.arin.net. The IANA has well-established working relationships with the US Government, the Internet Society (ISOC), and the InterNIC. ISOC provides coordination of IANA activities with the Internet Engineering Task Force (IETF) through the participation of IANA in the Internet Architecture Board (IAB). IANA responsibility was assigned by DARPA (Defense Advanced Research Project Agency) to the Information Sciences Institute (ISI) of the University of Southern California. ISI has discretionary authority to delegate portions of its functions to an Internet Registry (IR), previously performed by SRI International and currently performed by Network Solutions Inc. (NSI), a subsidiary of SAIC. Beginning March 1998, that function is shared with the Council of Registrars (CORE). CORE contracted (November 1997) with Emergent Corporation to build and operate the new Internet Name Shared Registry System (SRS), which is a neutral, shared database repository that coordinates registrations from CORE and propagates those names to the global Internet Domain Name System (DNS). www.isi.edu/div7/iana/ See also ARIN, CORE, DNS, Internet, InterNIC, and SRS.

Internet Backbone

This super-fast network spanning the world from one major metropolitan area to another is provided by a handful of national Internet Service Providers (ISPs). These companies and organizations use connections running at on T-3 lines and above linked up at specified interconnection points called national access points. Local ISPs connect to this backbone through routers so that data can be carried though the backbone to its final destination. The largest backbone operators include AT&T and WorldCom's UUNET Interconnection between these backbone operators is done through peering arrangements. Tele2 (based in Sweden) is one of few Pan-European fixed line operators that re-sell voice and Internet services to residential users, without owning a backbone network (but leases it instead).

Internet Cable Access

A general term used to describe accessing the Internet using the cable TV coaxial cable for inbound Internet access (i.e. downstream) and the phone line for up sending commands and requests (i.e. upstream information). The cable TV is very fast ” as much as six million bits per second. The phone is relatively slow ” no more than fifty thousand bits per second. But it works because most information from the Internet flows at you, not away from you. The cable and telecom industry is working on standards to make disparate cable systems and TV set-top boxes work with each other. The industry has developed Data Over Cable Service Interface Specification (DOCSIS), which sets standards for both two-way and cable-plus-phone specifications. See DOCSIS.

Internet Cache Protocol

See ICP.

Internet Call Waiting

Imagine you have one phone line at your house. You're presently using that one line to surf the Internet. Someone calls you. You have installed call forwarding. Their incoming call gets forwarded to another phone line, which is answered by a service provider who is providing the Internet call waiting service. Their machine answers: "The number you called is presently surfing the Internet. Would you like to tell them you're calling? Do you have a message? Record now." The machine picks up the incoming phone line from callerID, records the message and then sends an email to you, saying this phone number is trying to reach you. And here's their message." It then plays the message.

Internet Content Adaptation Protocol

See ICAP.

Internet Content Provider

ICP. A company that will design and deliver content for your Web site.

Internet Control Message Protocol

ICMP. An integral part of IP (Internet Protocol), ICMP is a mechanism by which IP software on a host or gateway can communicate with its peers on other machines to report errors and pass other information (e.g., time stamps) relevant to IP packet processing. As specified in RFC-792, ICMP also provides a number of diagnostic functions. One of the most frequently used ICMP messages is the Echo Request, commonly known as the Ping utility, which allows a device to test the communication path to another device. The ICMP header comprises 12 octets. See also Ping.

Internet Engineering Planning Group

See IEPG.

Internet Engineering Steering Group

IESG. The executive committee of the IETF (Internet Engineering Task Force).

Internet Engineering Task Force

IETF. One of two technical working bodies of the Internet Activities Board. The IETF is the primary working body developing new TCP/IP (Transmission Control Protocol/Internet Protocol) standards for the Internet. It has more than one thousand active participants . www.ietf.org.

Internet Fax

Internet fax is, as it sounds, sending faxes over the Internet. There are a whole bunch of manual ways to send faxes over the Internet ” most of which are akin to sending a fax over the PSTN, as we do it today. Dial up, etc. There are movements, however, to automate this process and get Internet faxing more along the lines of Internet email. Internet Fax is coming in two parts. The first is a store and forward model that is essentially based on the MIME attachment of TIFF files to standard E-Mail messages delivered by SMTP. The standards for this model are found in the IETF - ITU agreements of January 1998. The second part is an Internet draft that extends SMTP itself. The draft turns a fax machine into a virtual SMTP server so that transmission of the fax from point-to-point happens in real time. The protocol would extend SMTP beyond its function of a simple mail transport protocol to the point where, when a transport session is established, the user can exchange capabilities between devices - something that cannot be done with store and forward mail. Implementing these will be a series of hybrid "stupid-smart" devices that bridge faxes between the PSTN and the Internet. The Panasonic FO-770I, which is already on the market, is one such device with almost all the capabilities of the new standard . Load your fax, toggle "send" in one direction to transmit via the PSTN, toggle "send" in the other direction to go via the Internet. Other manufacturers are working on the introduction of inexpensive "black boxes" to connect standard G3 faxes in small-office, home-office (SOHO) environments directly to one's PC and from there to the Internet.

Internet Fax Protocol

IFP is specified in ITU-T recommendation T.38 as the method for supporting facsimile transmissions over IP (Internet Protocol) networks. See also T.37 and T.38.