Correlating Communication Sessions

A session handling entity in a communication system, comprising:

• maintaining means for maintaining a relationship between at least one public user identity, at least one private user identity and at least one contact address of a user of a communication system, wherein the maintained relationship comprises at least one Circuit Switched identity of the user and at least one IP Multimedia Subsystem (IMS) identity of the user,
• receiving means for receiving from a subscription entity an indication of a correlation identity associated with the user,
• storing means for storing the indication of the correlation identity as part of the relationship maintained by the maintaining means,
• session means for receiving a session request of the user
• determining means for determining the correlation identity for the user based on a contact address of the user included in the session request and the indication of a correlation identity associated with the user, and
• including means for including the correlation identity in the session request to correlate a Circuit Switched call to a session initiation protocol (SIP) session.

A method of correlating sessions in a communication system, comprising:

• maintaining a relationship between at least one public user identity, at least one private user identity and at least one contact address of a user of a communication system, wherein the maintained relationship comprises at least one Circuit Switched identity of the user and at least one IP Multimedia Subsystem (IMS) identity of the user,
• receiving from a subscription entity an indication of a correlation identity associated with the user,
• storing the indication of the correlation identity as part of the maintained relationship,
• receiving a session request of the user
• determining the correlation identity for the user based on a contact address of the user included in the session request and the indication of a correlation identity associated with the user, and
• including the correlation identity in the session request to correlate a Circuit Switched call to a session initiation protocol (SIP) session.