The purpose of the Call identity information element is to identify the suspended call. The call identity provided by the user is guaranteed by the network to be unique over the user-network interface on which the user resides. The call identity is assigned at the start of the call suspension, and is available for re-use after the resume procedure has completed successfully.
The Call identity information element is coded as shown in Figure 4-12.
The default maximum length of this information element is ten octets.