Session Manager Routing Stages - Nortel 5100 User Manual

• A domain, subdomain, or subscriber has access to the routes if the assigned
CoS permits access to the routes.
The domain-based CoS value is used to determine the telephony routes for
incoming sessions from gateways or other SIP networks. In these scenarios the
Uniform Resource Identifier (URI) domain does not host the originator so for the
security purposes the CoS of the URI domain is applied to screen the call.
• If the From: header and Request URI: do not have the same domain, then the
domain specified in the Request URI: determines the telephony routes.
• If the From:, To:, and Request URI: domains are the same, and the originator
is an MCP subscriber, then the originator's CoS determines the telephony
routes. If the originator does not have an assigned CoS, then the CoS for the
originator's subdomain is used. If the subdomain does not have an assigned
CoS, then the call cannot access any telephony route.
• The same CoS values can be assigned to a domain, subdomain, and a
subscriber.

Session Manager routing stages

The following figure shows the relationship between the telephony routing stages
provided by the Session Manager. If the CoS value of the subscriber and
subdomain route do not match, then the parent and subsequent subdomains are
checked for routes that permit access.
Provisioning Client User Guide
219