8.7 GA-CSR Connection handling

3GPP43.318Generic Access Network (GAN)Release 17Stage 2TS

The GA-CSR connection is a logical connection between the MS and the GANC for the CS domain. It is established when the upper layers in the MS request GA-CSR to enter dedicated mode. When a successful response is received from the network, GA‑CSR replies to the upper layer that it has entered dedicated mode. The upper layers have then the possibility to request transmission of NAS messages to the network.

8.7.1 GA-CSR Connection Establishment

Figure 17 shows successful establishment of the GA-CSR Connection.

Figure 17: GA-CSR Connection Establishment

1. The MS initiates GA-CSR connection establishment by sending the GA-CSR REQUEST message to the GANC. This message contains the Establishment Cause indicating the reason for GA-CSR connection establishment.

2. GANC signals the successful response to the MS by sending the GA-CSR REQUEST ACCEPT and the MS enters dedicated mode and the GA-CSR state changes to GA-CSR-DEDICATED.

3. Alternatively, the GANC may return a GA-CSR REQUEST REJECT indicating the reject cause.

8.7.2 GA-CSR Connection Release

Figure 18 shows release of the logical GA-CSR connection between the MS and the GANC.

Figure 18: GA-CSR Connection Release

1. The CN indicates to the GANC to release the user plane connection allocated to the MS, via the Clear Command.

2. The GANC confirms resource release to CN using the Clear Complete message.

3. The GANC commands the MS to release resources, using the GA-CSR RELEASE message.

4. The MS confirms resource release to the GANC using the GA-CSR RELEASE COMPLETE message and the MS enters idle mode and the GA-CSR state in the MS changes to GA-CSR-IDLE.