Lucent Technologies 5ESS User Manual

From the viewpoint of the 5ESS
®
switch TPS, when the calling party
(either in the IP network if the TPS is a PSTN Gateway, or in the
PSTN for SIP packet trunking between PSTN offices) goes on-hook:
1. The TPS receives a SIP BYE message.
2. The TPS formulates an ISUP REL message and forwards it to the
terminating switch. The TPS also tears down the call and releases
resources dedicated to the call.
Tearing Down Call Path
This section overviews tearing down of a SIP call from a high-level
view. In this scenario, the calling party ended the call by going
on-hook.
1. The calling party goes on-hook. The originating switch send an
ISUP REL message to the OPS to notify the OPS of the state
change.
2. The OPS formulates a SIP BYE messages and forwards it to the
TPS. The OPS also tears down the call and releases resources
dedicated to the call.
High-Level Call Flow
Call Flow
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235-200-118
Issue 3.02B, March 2007
Lucent Technologies
3-13

Lucent Technologies 5ESS Specifications

General

Brand	Lucent Technologies
Model	5ESS
Category	Switch
Language	English