Example 2 describes calls between two SIP stations within the same Session Manager instance with different Communication Managers administered as either a feature server or evolution server.

Call between two SIP stations with same Session Manager instance and different Communication Managers shows the signaling flow associated with a call between two SIP stations registered to the same Session Manager instance and using different feature servers, different evolution servers, or one of each.

Session Manager resources associated with the call depicted in Figure : 1 include:

• 3 SIP sessions

  • SIP A - Session Manager - Communication Manager

  • Communication Manager - Session Manager - Communication Manager

  • Communication Manager - Session Manager - SIP B

Communication Manager resources associated with each Communication Manager for the call depicted in Figure : 1 include:

• 2 SIP trunk channels (for either feature server or evolution server)

• CPU for 2 SIP trunk call legs (for either feature server or evolution server)