It goes without saying that, between two endpoints on a network, there must be an agreement on the protocol, or language, that is in use. There is some irony in the fact that the same requirement is sometimes ignored when the communications endpoints are the network administrator and the z/OS system programmers.

It is not unheard of to have the network administrator maintain that the problem is with the data link control, only to have the system programmer reply that there have been no linkage errors with any programs.

And this is a significant issue; the amount of information that network administrators and systems programmers must know in order to do their jobs is enormous. While each specialist has a clearly defined domain, some overlap is required. This section presents brief summaries of key terms that you need to understand in order to communicate with a network administrator.

This part deals primarily with IP-related networking terminology, but there is a brief topic on System Network Architecture (SNA). SNA topics are covered in more detail in the topics on SNA-basics and implementation, SNA Advanced Peer-to-Peer Networking (APPN), and SNA/IP implementation.