Other Network Protocols of Note

With TCP/IP serving as the de facto network protocol and many legacy networks (another way of saying "old networks") running IPX/SPX, some very fast and clever network protocols have kind of fallen by the wayside. Let's take a look at some other network protocols that you can still use and that will certainly be found on networks running in some environments.


NetBIOS Extended User Interface (or NetBEUI ) is a simple and fast network protocol that was designed to be used with Microsoft's and IBM's NetBIOS (Network Basic Input Output System) protocol on small networks. NetBIOS is a protocol that allows computers to be identified on the network by a friendly name . Anyone who has ever set up a version of Microsoft Windows has experienced setting up a computer name during the installation of the Windows software.

Although it's an excellent transport protocol that doesn't require a whole lot of resources from a computer or the network to move data, NetBEUI is not a routable protocol; therefore, it cannot be used on large networks where routers are used to move data between the various segments or subnets. As far as protocol concepts go, NetBEUI operates at the Transport and Network layers of the OSI model.

With the release of Windows XP, Microsoft no longer supports NetBEUI as a default network protocol. It is not listed when you attempt to add a protocol to the connection Properties dialog box of a computer running Windows XP (or Windows Server 2003). For information on adding NetBEUI to a Windows XP computer see the link http://support.microsoft.com/default.aspx?scid=kb;en-us;Q301041&sd=tech. It provides all the steps for installing NetBEUI as a network protocol.


In the first decade or so of the PC revolution, the Macintosh computer definitely had a leg up on the DOS/Windows environment as far as networking was concerned because of the AppleTalk protocol stack. AppleTalk was (and still is) extremely easy to configure, and the hardware required for network connectivity (called LocalTalk ) was built into each and every Macintosh (Mac computers, including the new iMac, still come with all the networking hardware required; however, their configuration is now slanted toward Ethernet and TCP/IP).

AppleTalk is a routable protocol that allows large networks to be broken into logical subgroups called zones . A zone is a collection of certain users (which do not have to be located at the same physical location) and is similar to the concept of workgroups in Microsoft peer-to-peer networking (we will explore Microsoft workgroups in Chapter 6). Users in a zone typically share the same network resources, such as files and printers.

AppleTalk Addressing

AppleTalk also uses a two-part network addressing system (as do TCP/IP and IPX/SPX). This address is divided into a network portion and a node (or computer) portion.

The network number is actually specified by the network administrator. Because it is a logical addressing system, decimal numbers can be used to identify the different AppleTalk logical networks that reside on the actual physical network. For example, a logical network that takes up an entire physical network could be assigned the network number 10 by the administrator. If several different AppleTalk networks were to be assigned to one physical network, the administrator could designate them as a numerical range, such as 1020.

Node addresses are extremely easy to configure because you don't actually configure them at all. When a Macintosh client is brought up on the AppleTalk network, it generates a random node number and broadcasts it out onto the network to let the other computers know that it is going to use that number. This serves as the node address for the computer. The logical network number created by the administrator (such as 10, as in the preceding example) and the random node address that is generated by the computer make up the complete network address for the computer.



If the node address generated by a computer on an AppleTalk network is already taken, the computer will generate a new node address and broadcast this to the other computers on the network.

AppleTalk and the OSI Model

The AppleTalk protocol stack is made up of a number of protocols that supply all the features required for network communication. Table 5.5 provides a list and brief definition of some of the AppleTalk protocol stack members .

Table 5.5. AppleTalk Protocol Stack Members




AppleShare provides services at the Application layer.


The AppleTalk Filing Protocol provides and manages file sharing on the network.


The AppleTalk Transaction Protocol works at the Transport layer and manages the connection between computers.


The Name Binding Protocol maps computer hostnames to Network layer addresses.


The Zone Information Protocol controls AppleTalk zones and maps zone names to network addresses.


The AppleTalk Address Resolution Protocol maps logical Network layer addresses to Data Link hardware addresses.


The Datagram Delivery Protocol provides the logical addressing system for the AppleTalk network.


Before we completely end this discussion of network protocols, I should mention the Data Link Control protocol (or DLC ). DLC was actually developed for communication between mainframes and Hewlett-Packard (HP) printers. You might run into DLC in situations where you have printers directly connected to a network (rather than connected to a computer on the network) using an HP Jet Direct box or HP Jet Direct card. Typically, printers connected using these devices will be assigned an IP address like any other node on the network.

However, if you are using HP Jet Direct-enabled printers on a network that is not using TCP/IP, you must use DLC for the printer or printers to communicate with the computers on the network. DLC can be configured on Windows-based computers. DLC is also configured on the printers using installation software that is provided with the HP Jet Direct box or card.



Mac computers are now geared up to use TCP/IP as their network protocol. You can still use AppleTalk on networks that do not need to be connected to the Internet.

The Absolute Minimum

This chapter has provided a discussion of conceptual network models, particularly the OSI model. We also had the opportunity to sort out the differences between different LAN protocols and how they relate to the OSI conceptual model.

  • Network protocol stacks are used by computers to communicate on the network.

  • The OSI model provides a conceptual model for network communication and data transfer.

  • The OSI model is divided into seven layers; each layer takes care of specific duties related to network communication.

  • The TCP/IP protocol stack has become the standard for computer networking because of the Internet.

  • TCP/IP is actually a stack of protocols, and each protocol takes care of certain processes involved in network communication.

  • The IP protocol provides the logical addressing system used on TCP/IP networks.

  • An IP address is a 32-bit, four-octet address.

  • Three classes of address, A, B, and C, are available for assigning addresses to TCP/IP networks. Class A is used for very large networks, Class B for medium-size networks, and Class C for small networks.

  • IPX/SPX is another routable protocol stack; it is typically used on networks running the Novell NetWare NOS.

  • IPX is the protocol in the IPX/SPX protocol stack that handles the logical addressing system for the network.

  • IPX addresses provide both network and node information. The network portion of the address is generated by the NetWare server, and the node address is the MAC hardware address of the computer.

  • AppleTalk is a protocol stack created by Apple and used on Apple Macintosh networks. AppleTalk node addresses are created by a Macintosh computer the first time it connects to the network.

  • DLC is a protocol that can be used to communicate with Hewlett-Packard printers directly connected to the network. It is used in situations where TCP/IP is not in use on the network.

Absolute Beginner's Guide to Networking
Absolute Beginners Guide to Networking (4th Edition)
ISBN: 0789729113
EAN: 2147483647
Year: 2002
Pages: 188
Authors: Joe Habraken

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