APPN session endpoint is one hop from the interchange node

If the session is from a subarea node through an interchange node to an end node that is one hop away from the interchange node, translation of subarea to HPR can occur. In Figure 1, for example, a session can exist between LUA and LUB, and HOSTB will translate subarea data received from HOSTA to HPR and route it across the RTP connection to HOSTC.

Figure 1. Interchange node using HPR routing between subarea and APPN

Similarly, if the session is from a subarea node through an interchange node to a network node that is one hop away from the interchange node, translation of subarea to HPR can occur if the interchange node is IBM® Communications Server for OS/390® V2R10 or later and the network node is one of the following types:

A network node with IBM Communications Server for OS/390 V2R10 or later installed
A non-z/OS® Communications Server network node

For instance, in Figure 1, if HOSTC were a network node, HOSTB will translate subarea data received from HOSTA to HPR and route it across the RTP connection to HOSTC, provided that HOSTB and HOSTC meet the above criteria.