This section provides information about how the Dial Plan Transparency (DPT) feature behaves in certain circumstances. Use this information to ensure that you receive the maximum benefits of Dial Plan Transparency under all conditions. The following considerations apply to Dial Plan Transparency:
DPT only handles WAN connectivity failures between Network Regions. DPT does not cover the following cases:
Two Gateways in the same Network Region, registered to the same server (main or Survivable Remote Server or Survivable Core Server), cannot reach each other due to LAN congestion or failure. Note that this case cannot be handled by IGAR either.
A Gateway becomes disconnected from the main server and cannot register with an Survivable Remote Server or Survivable Core Server at all. In such a case the gateway will enter Standard Local Survivability mode, which provides basic call processing functionality during the outage.
Failover strategies for Gateways and Port Networks, and alternate gatekeeper lists for IP stations must be in harmony. DPT does not work in the following scenarios:
Two Gateways or Port Networks in the same Network Region register to different Survivable Remote Server or Survivable Core Server servers during a network outage.
Two IP endpoints in the same Network Region register to different servers during a network outage.
Because DPT calls are trunk calls, most station features cannot be supported. DCS and QSIG features are not supported, even if the trunk carrying the DPT call supports DCS or QSIG. Communication Manager displays a new reason code to alert users about the reduced functionality.
