1. User's Guide
  2. Registrar and Authentication
  3. Register Refresh

Register Refresh

When a UA sends a register refresh, the Oracle Enterprise Communications Broker first confirms that the authentication exists for that UE’s registration cache entry, and then is valid for the REGISTER refresh. (If a valid hash does not exist for that AoR, then the Oracle Enterprise Communications Broker sends a request to its source database (LST or LDAP) to retrieve authentication data once again).

Next, the Oracle Enterprise Communications Broker determines it can perform a local REGISTER refresh or if the source database needs to be updated. If any of the following 3 conditions exists for the re-registering UA, the Oracle Enterprise Communications Broker updates the database:

  • The location update interval timer has expired—This value, configured in the sip registrar configuration element ensures that source database always has the correct Oracle Enterprise Communications Broker address by periodically sending request messages for each registered contact.
  • The message’s call-id changes while the forward-reg-callid-change option in the sip config configuration element is set. This covers the case where the UA changes the Oracle Enterprise Communications Brokers through which it attaches to the network.
  • The REGISTER message’s Cseq has skipped a number. This covers the case in which a user registered with Oracle Enterprise Communications Broker1, moves to Oracle Enterprise Communications Broker2 , and then returns to Oracle Enterprise Communications Broker1.

If the Oracle Enterprise Communications Broker updates the source database because of matching one of the above conditions, the access side expiration timer per contact is reset to the REGISTER message’s Expires: header value, and returned in the 200 OK. This happens even in the case when the reREGISTER was received in the first half of the previous Expires period. In addition, the core-side location update interval timer are refreshed on both active and standby.

When the above three conditions are not met, the registration expiration proceeds normally.

If the timer has not exceeded half of its lifetime, a 200 OK is returned to the UA. If the timer has exceeded half of its lifetime, the Oracle Enterprise Communications Broker just refreshes the access-side expiration timer; the registration cache expiration timer for that AoR begins its count again.