Advanced Peer-to-Peer Networking (APPN)

An Advanced Peer-to-Peer Networking (APPN) network is composed of a group or groups of connected T2.1 nodes. T2.1 nodes provide sessions between LUs and peer-level connectivity using the APPC protocol. Unlike hierarchical SNA subarea networks, sessions between two APPN or low-entry networking nodes can be established without involving a mainframe in the session setup.

APPN nodes:

Search and keep track of SNA resource locations within the network
Dynamically exchange information about the resource location they own, eliminating the need to pre-define resources owned by other nodes
Maintain knowledge of APPN network topology (the APPN nodes and the links between them) and use this information to select the best available path to route sessions between SNA resources, thereby eliminating the need for complex path definitions