Site home page
(news and notices)

Get alerts when Linktionary is updated

Book updates and addendums

Get info about the Encyclopedia of Networking and Telecommunicatons, 3rd edition (2001)

Download the electronic version of the Encyclopedia of Networking, 2nd edition (1996). It's free!

Contribute to this site

Electronic licensing info



APPN (Advanced Peer-to-Peer Networking)

Related Entries    Web Links    New/Updated Information

Search Linktionary (powered by FreeFind)

Note: Many topics at this site are reduced versions of the text in "The Encyclopedia of Networking and Telecommunications." Search results will not be as extensive as a search of the book's CD-ROM.

IBM's APPN was introduced by IBM in 1985 and integrated into SNA (Systems Network Architecture). It provides peer-to-peer networking services similar to but not quite the same as TCP/IP. One of the main reasons IBM introduced APPN was to provide distributed client/server computing services to users who might have moved to TCP/IP or other services. APPN is basically link-layer independent. It can run over token ring, Ethernet, FDDI, frame relay, ISDN, X.25, SDLC, and ultra high-speed networks such as B-ISDN and ATM.

APPN is based on the concept that computers on the network have enough processing power of their own to handle session management and routing. APPN moves various services from central control (such as that provided by a host mainframe computer) to decentralized control points that operate in a peer-to-peer relationship. In the old SNA model, a mainframe was required to control sessions. In the APPN model, user stations set up and maintain their own sessions.

This topic continues in "The Encyclopedia of Networking and Telecommunications" with a discussion of the following topics:

  • APPN/OSI comparison
  • APPN routing services
  • ENs (end nodes), NNs (network nodes), CNN (composite network nodes), LENs (low-entry nodes), BNs (border node), and EBNs (extended border nodes)
  • CPI-C (Common Programming Interface for Communications) applications interface
  • APPN developments
  • DLSw (Data Link Switching)
  • RFC 2353 (APPN/HPR in IP Networks, May 1998)


Copyright (c) 2001 Tom Sheldon and Big Sur Multimedia.
All rights reserved under Pan American and International copyright conventions.