Circuit Group Query

Circuit Group Query from the Network

Here, the network initiates a circuit group query by sending a Circuit Query message (CQM). HP OpenCall SS7 ISUP can process the request internally without interfering with the application. Therefore, no indication is issued to the latter. Each circuit of the group selected is examined, and its status is returned in the Circuit State Indicator parameter of the Circuit Query Response Message (CQR). If the circuit is not found, it is considered unequipped.

rangeAndStatus parameter interpretation:

Figure 20-17 Circuit Group Query - from Network

Circuit Group Query from Application

For ITU-T based HP OpenCall SS7 ISUP, the application is allowed to activate a circuit group query procedure by creating a message, and sending it to the network associated with a GROUP_QUERY_REQ primitive.

HP OpenCall SS7 ISUP starts a Timer dedicated to the group query procedure:

Normal Case

On receipt of the answer to the CQM from the network, the received CQR message is transmitted to the application by HP OpenCall SS7 ISUP through a GROUP_QUERY_CONF primitive.

Figure 20-18 Circuit Group Query from User - Normal Case

Failure to Receive CQR

If the timer expires, HP OpenCall SS7 ISUP sends back a MAINTENANCE_SYSTEM_IND primitive indicating:

• the T34_TIMEOUT for the ITU-T 88 version

• the T28_TIMEOUT for all other ITU-T based flavors

Figure 20-19 Circuit Group Query from User - Failure