DDNS Update to User Subscriber Database

As REGISTER messages are received, the Oracle Communications Unified Session Manager updates the ENUM database via DDNS UPDATE messages as defined by RFC2136. New registrations are added to the database while expired or deleted registrations are removed.

The Oracle Communications Unified Session Manager acts as a registrar by configuring the sip registrar configuration element. When registrar functionality is enabled, the Oracle Communications Unified Session Manager acts as a registrar rather than only caching and forwarding registrations to another device. Oracle Communications Unified Session Manager registry services are enabled globally per domain, not on individual SIP interfaces or other remote logical entities.

On receiving a REGISTER message, the Oracle Communications Unified Session Manager checks if it is responsible for the domain contained in the Request-URI as defined by the domains parameter and finds the corresponding sip registrar configuration. This is a global parameter and all messages are checked against all sip registrar domains. Thus you could create one sip registrar configuration element to handle all *.com domains and one sip registrar configuration element to handle all *.org domains. The Oracle Communications Unified Session Manager begins registrar functions for all requests that match the configured domain per sip-registrar configuration element.

A UA is considered registered after the Oracle Communications Unified Session Manager updates the ENUM server with a DDNS dynamic update. After this action, the Oracle Communications Unified Session Manager sends a 200 OK message back to the registering UA.