Section: 5.2.2.7 Traffic channel assignment at mobile terminating call establishment
Content: After receiving the SETUP message, the mobile station supporting multicall may either require a new traffic channel or reuse an existing traffic channel. If a mobile station in the network supporting multicall requires a new traffic channel, it shall: - send a CALL CONFIRMED message including the SI indicating a new value, not used by any of the existing traffic channels. If a mobile station in the network supporting multicall does not require a new traffic channel, it shall: - send a CALL CONFIRMED message including the SI equal to "no bearer". After the mobile station has send the CALL CONFIRMED with SI="no bearer", the SI value in the CONNECT message will tell to the network if a user requests a new traffic channel or one of the existing ones will be re-uesd. If a new traffic channel is requested by the user, the mobile station in the network supporting multicall shall: - send a CONNECT message containing the SI with a new value, not used by any existing traffic channel. If the user decides that an existing traffic channel will be reused, the mobile station in the network supporting multicall shall: - send a CONNECT message with an SI indicating an existing value used by an existing traffic channel. It is a network dependent decision when to initiate the assignment of a traffic channel during the mobile terminating call establishment phase. Initiation of the assignment phase does not directly change the state of a CC entity nor affect any call control timer, but may have some secondary effects (see e.g. subclause 5.2.2.3.2).