If the subarea network is set up as a communications management configuration (CMC) with multiple VTAMs acting as CMCs, there must be enough VR-based TGs and CP-CP sessions defined between the CMCs to satisfy network availability requirements, based on the considerations described earlier. Although some redundant VR-based TGs and CP-CP sessions might have to be defined, to provide connectivity to all network nodes when TGs carrying CP-CP sessions fail abnormally, meshed VR-based TGs and CP-CP sessions between every pair of VTAM® nodes will rarely be required, even when every VTAM is physically adjacent to every other VTAM.