Dialogic 6.2 manual Isdn Call Clearing Initiated by Network, November 325

ISDN Call Processing Overview

If you want manual control over the sending of RELEASE

COMPLETE, set the field below to 1:

l43.data.enable_protocol.level3.cnfg.q931.release_complete_control = 1

An L4L3mCLEAR_REQUEST message will then send the RELEASE COMPLETE message.

The host cannot consider a call disconnected and the channel available for another call until the L3L4mCLEAR_REQUEST message has been received from the module.

If the call is made using Switched 56 robbed bit signaling (not ISDN), there is an additional waiting period between sending the L4L3mCLEAR_REQUEST and receiving the L3L4mCLEAR_ REQUEST indicating the channel is available. This interval is equal to the value of the guard_interval_timer and is usually 100 ms. Refer to Chapter , Robbed Bit Signaling on page 264 for more information on robbed bit signaling timers.

ISDN Call Clearing - Initiated by Network

A typical ISDN call clearing is illustrated in Figure 51. In this call scenario, the module responds to the network’s request to disconnect a call. The following message exchange is relative to the module:

1.The network initiates the call clearing procedure by sending a DISCONNECT message to the module.

2.Upon receipt of the DISCONNECT, the module generates an L3L4mDISCONNECT message to the host indicating the network is clearing the call.

3.The host responds with an L4L3mCLEAR_REQUEST message indicating the call should be cleared.

4.Upon receipt of the L4L3mCLEAR_REQUEST, the module generates a RELEASE message to the network.

5.The network responds to the received RELEASE by generating a RELEASE COMPLETE message.

6.Upon receipt of the RELEASE COMPLETE message, the module informs the host the call has been cleared using the L3L4mCLEAR_REQUEST message.

It should be noted that the host cannot consider a call disconnected and the channel available for another call until the L3L4mCLEAR_ REQUEST message has been received from the module.

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