At the connection end where suspension was initiated, the user may request re-establishment of a call after physical reconnection of a terminal by sending a RESUME message containing the call identity exactly as that used at the time of call suspension; starting timerT318 and entering the Resume Request state. If the SUSPEND message did not include a Call identity information element, then the corresponding RESUME message shall also not include a Call identity information element. The call reference included in the RESUME message is chosen by the user according to the normal allocation of outgoing call reference (see 4.3).
On receipt of a RESUME message, the network enters the Resume Request state. After a positive validation of the call identity that relates to the suspended call containing a valid identity that relates to a currently suspended call, the network shall, send a RESUMEACKNOWLEDGE message to the user; release the call identity; stop timer T307 and enter the Active state. The RESUME ACKNOWLEDGE message shall specify the B-channel reserved to the call by the network by means of the channel identification element, coded B-channel is indicated, no alternative is acceptable.
The network shall also send a NOTIFY message with the notification indicated user resumed to the other user.
No memory of the previously received call identity sequence is kept by the network after sending the RESUME ACKNOWLEDGE message. This call identity is now available for another suspension.
On receipt of the RESUME ACKNOWLEDGE message., the user shall, stop timer T318 and enter the Active state.
No compatibility is performed during the call arrangement phase.