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IN STRICTEST CONFIDENCE
BT Wholesale
Issue 1: 2012© British Telecommunications plc
Page 5 of 33
IN STRICTEST CONFIDENCE
8.5
COS ......................................................................................................................................................... 27
8.6
Trunk to Trunk Routing - Optional ............................................................................................................. 28
Trunk to Trunk Transfer ............................................................................................................................................ 28
External Call Forward -COS....................................................................................................................................... 28
Trunk to Trunk Options ............................................................................................................................................ 28
8.7
Dialing Plan ............................................................................................................................................. 29
9
TROUBLESHOOTING AND USEFUL INFORMATION ............................................................. 30
9.1
Checking SIP Messaging To/From the PBX .................................................................................................. 30
9.2
Device Fails to Register ............................................................................................................................ 31
9.3
Outbound Calls Fail .................................................................................................................................. 32
9.4
Inbound Calls Fail ..................................................................................................................................... 33