Abstract: Enhanced type 2.1 nodes for SNA networks provide network routing of information between non-adjacent network nodes and program-to-program linkage across the network. These nodes are called "advanced peer to peer networking" (abbreviated APPN) nodes. Network state information, describing the topology and resources of the network is disseminated betweeen APPN nodes by a first data link control exchange of identification (XID) information indicating node type (and thereby distinguishing APPN nodes from other nodes) and other exchanges conducted over a newly defined control point to control point (abbreviated CP--CP) session having a message architecture unique to APPN type nodes. The XID exchange is conducted whenever a link between nodes is activated, and when the exchanging nodes are both APPN, and if both are available to participate in as CP--CP session, they automatically engage in a second exchange of session binding signals which establish a pair of sessions between the nodes.

Abstract: A LOCATE search dynamically locates resources (e.g., logical units (LUs) and transaction program and files associated with LUs) in a computer network so that a session can be established between the origin and the destination of the search.In a network which includes end nodes associated with server nodes, a resource contained in any node is located by a requesting node. The requesting node initiates a search of the resources residing within itself. If the resource does not reside in the requesting node, the server node searches the resources known to the server node that reside anywhere in the nework. If the resource is not known by the server node, it searchers all resources that reside in its associated end nodes. If the resource does not reside in the associated end nodes, either a request is sent to a central directory if one exists or a search of all resources in the network is made.

Abstract: When computing a least weight path from an origin node to a destination node in a data communication network, a route-computing network node uses information provided by the origin and destination nodes to compute least weight routes from those nodes to adjacent network nodes. The route-computing network node uses information in the topology database to compute least weight routes from network nodes adjacent the origin node to network nodes adjacent the destination node. The results of the computations are concatenated to determine an optimum route from the origin node to the destination node. The topology database need not include information about the transmission groups connecting the origin/destination nodes to network nodes.