User`s manual

Version 5.4 459 May 2008
SIP User's Manual 9. Advanced PSTN Configuration
9 Advanced PSTN Configuration
9.1 Clock Settings
The device's clock settings can be configured to either generate its own timing signals, use
an internal clock, or recover them from one of the E1/T1 trunks.
¾ To use the device's internal clock source, configure the following
parameters:
 TDMBusClockSource = 1
 ClockMaster = 1 (for all trunks)
¾ To use the recovered clock option, configure the following
parameters:
 TDMBusClockSource = 4
 ClockMaster_x = 0 (for all ‘slave’ trunks connected to PBX#1)
 ClockMaster_x = 1 (for all ‘master’ trunks connected to PBX#2)
The above assumes that the device recovers its internal clock from one of the ‘slave’ trunks
connected to PBX#1 and provides clock to PBX#2 on its ‘master’ trunks.
In addition, it's necessary to define from which of the ‘slave’ trunks the device recovers its
clock:
 TDMBusPSTNAutoClockEnable = 1 (device automatically selects one of the
connected ‘slave’ trunks)
- Or -
 TDMBusLocalReference = # (Trunk index: 0 to 3, default = 0)
Notes:
• To configure the TDM Bus Clock Source parameters using the Web
interface, refer to ''Configuring the TDM Bus Settings'' on page 251.
• When the device is used in a ‘non-span’ configuration, the internal device
clock must be used (as explained above).
9.2 Release Reason Mapping
This section describes the available mapping mechanisms of SIP Responses to Q.850
Release Causes and vice versa. The existing mapping of ISDN Release Causes to SIP
Responses is described in ''Fixed Mapping of ISDN Release Reason to SIP Response'' on
page 460 and ''Fixed Mapping of SIP Response to ISDN Release Reason'' on page 462.
To override this hard-coded mapping and flexibly map SIP Responses to ISDN Release
Causes, use the ini file (CauseMapISDN2SIP and CauseMapSIP2ISDN, as described in
''ISDN and CAS Interworking-Related Parameters'' on page 348) or the Web interface
(refer to ''Release Cause Mapping'' on page 211).