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<h1>SCCP Improvement</h1>

<p>This feature improves the BSC A interface so that it can
more easily adapt to changes in the MSC signalling software. It consists of
the SCCP State Change Filtering Timer and Parameter Controlled Sending of
the Status Test Message (SST) features.</p>


<p>The SCCP State Change Filtering Timer feature makes the
A interface more tolerable against short cuts in the signalling connection:
only calls in signalling phase are cleared locally in case of SCCP status
change to unavailable and soon after that to available. An SCCP status change
may be caused by a short PCM failure, unit switchover, or an MTP failure.</p>


<p>The sending of the SST status test message fastens the
recovery of the signalling connection if the signalling point restart procedure
occurs, for example, due to a unit restart.</p>
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