SIP TRANSFER IN A BACK-TO-BACK USER AGENT (B2BUA) ENVIRONMENT

摘要

The system generates a change in the SIP INVITE message during a call transfer. Here, a user relation element involved in the call can change the header information in the message to include the endpoint view of the transferring party. Thus, the INVITE message is redirected to the transferring party's user relation element, which can interpret the received message and "unravel" the B2BUAs in the existing call path. The system includes changes in the user relation element to effect the message change and interpret the message once received. Changes to the user relation element forgo the need to change the communication endpoints.