As described previously, with HPR, you can migrate NCP connections to APPN connections without incurring the associated increase in storage and cycles. However, this is not always possible. In Figure 1, for instance, for a session between the terminal and HOSTB (an interchange node), HPR cannot be used (see Sessions through NCP in a composite network node providing RTP support for additional information). If APPN storage demands are unacceptable in such a situation, add a VR-based TG to connect the terminal and HOSTB through the subarea network, which allows them to act as APPN peers. Meanwhile, for sessions between HPR-capable endpoints, HPR routing can continue over the existing APPN connection.