PSTN Inbound (Originating Customer) Failover Routing
When the Peeredge Switch SBC receives a SIP Invite from an upstream PSTN Service Provider in the Dallas data center, the switch matches an Originating Customer Trunk Group based on the called party number in the SIP Invite. The Softswitch then builds a list of all active trunk members configured in this Trunk Group for Dallas and then forwards the SIP Invite to the trunk member (i.e. SBC/PBX) based on the configured Call Distribution.
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PSTN Outbound (Terminating Customer) Failover Routing
When the Peeredge Switch SBC receives a SIP Invite from a customer in the Dallas data center, it matches a Terminating Customer Trunk Group based on the customer’s SBC/PBX IP Address, Port, and Protocol (UDP, TCP, TLS). If no match is found, the Softswitch responds with a SIP 401 with a WWW-Authenticate header to allow for SIP Registration-based authentication. Once authenticated, the Softswitch routes the SIP Invite to all configured PSTN Provider Trunk Groups configured in Dallas.
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