23.2053GPPBearer-independent circuit-switched core networkRelease 17Stage 2TS
The mobile originating call shall be established in accordance with 3GPP TS 23.108 . The following clause describe the additional requirement for the bearer independent CS core network if a trace session is activated from a MSC Server to a MGW.
22.214.171.124 Trace activation
When a Trace Session is activated in the MSC Server and the trace control and configuration parameters requires Trace Session activation to the MGW, the MSC Server activates the Trace Session to the MGW by using the trace activation procedure.
Figure 126.96.36.199 shows the network model for the mobile originating call. The "squared" line represents the call control signalling. The "dotted" line represents the bearer control signalling (not applicable in A/Gb mode for the A-interface) and the bearer. The MSC server seizes one context with two bearer terminations in the MGW. The bearer termination T1 is used for the bearer towards the RNC/BSC and the bearer termination T2 is used for the bearer towards the succeeding MGW.
Figure 188.8.131.52: Basic Mobile Originating Call, Forward Bearer Establishment with Trace Session Activation (network model)
Figure 184.108.40.206 shows the message sequence chart example for the mobile originating call. In the example the MSC server activates the Trace Session to MGW when it request the creation of the incoming and outgoing termination with ADD request. MGW sends the Trace Session Activation result with NOTIFY request to MSC Server.
Figure 220.127.116.11/1: Basic Mobile Originating Call, Forward Bearer Establishment with Trace Session Activation
(message sequence chart)
Figure 18.104.22.168/2: Basic Mobile Originating Call, Forward Bearer Establishment with Trace Session Activation
(message sequence chart continue)