In our previous post, We introduced changes in Office Communications Server to enable Direct SIP with IP-PBX such as Cisco Call Manager in our previous post. This post provide a configuration of Direct SIP with Cisco Call Manager 4.2.1.
1. Main assumptions for the example:
Here are the main assumptions for this example:
- This is a single site, located in Paris, France (country code 33, local code 1).
- All PSTN calls, incoming and outgoing, from and to Cisco Call Manager and Office Communications Server, use the preexisting PSTN interconnection trunks that are connected to and managed by the Cisco Call Manager. All calls to and from Office Communications Server go across the SIP trunk between Cisco Call Manager and Mediation Server.
As discussed before, it is also possible (and eventually more effective, especially at large scale and for example with the use of SIP Trunking to Carrier) to have direct PSTN-out routes from Office Communications Server to the PSTN without going through the Cisco Call Manager. Also, in this example, we do not implement redundant routes between Cisco Call Manager and Office Communications Server; that is of course possible but exceeds the scope of this simple example.