Redirect Server (RS)
Redirect Server (RS)
- receives SIP REGISTER messages from User Agents (UAs)
- keeps track of registered users and their locations (i.e., registrations)
- provides routing information for SIP INVITE messages
- based on caller, callee, and registration information (for either or both parties)
- based on where the INVITE message has already been
- Supports redundancy
- Utilizes multicast heartbeat
- starts by listening for 2s for another RS
- if found, then it synchronizes with this RS and will act as a redundant backup RS (following synchronization)
- if not found, then it starts transmitting its own heartbeat
- a given RS must mirror REGISTER messages (received from the MS) to the other RSs
- Utilizes multicast heartbeat
Transcript
[slide523] They had a redirect server.