CertiGuide to Network+  9  Chapter 0100:  Network Protocols

Connection-Oriented vs. Connectionless Service 1 V  NetBEUI

IPX/SPX is the Internetwork Packet Exchange / Sequenced Packet Exchange protocol suite. These Novell Netware OS native protocols were inspired by the XNS protocols from XEROX PARC (Plato Alto Research Center). Using the analogy of cars, IPX is more than a little like a station wagon. That is, it has reasonable performance, and is flexible without a huge amount of overhead.

Since Netware was so popular, and the protocol so well designed, it has proven very popular. IPX is the default network communications protocol in Netware 2.x, 3.x and 4.x. TCP/IP has since replaced it in Netware 5, however it is still possible to use IPX with Netware 5.

IPX is fast because it is a connectionless protocol. When Netware needs the reliability of a full connection, it uses the Sequence Packet Exchange (SPX), which operates at the transport layer. Like IP, IPX supports datagram services.

Typically, IPX packets are just over 4K in size (4202 bytes). A point to remember for almost any network test as well as for real life is that in the long life of the IPX protocol it has gone through minor but important changes.

By default, the header for IPX functioned in one fashion in Netware through versions 3.11. The next version of Netware 3.12, Novell made a change in frame type to accept industry standards.

Connection-Oriented vs. Connectionless Service 1 V  NetBEUI