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IN STRICTEST CONFIDENCE
BT Wholesale
Issue 1: 2012© British Telecommunications plc
Page 7 of 33
IN STRICTEST CONFIDENCE
2
IPVS Source Numbering Requirements
Please note that the following prerequisites must be satisfied for successful deployment:
Any SIP call must present a number with a current registration on the IPVS platform in one or more of
the following headers of the SIP message transmitted by the IP-PBX (listed in order of significance):
1. Diversion
2. P-Asserted-Identity
3. Remote-Party-Id
4. From
If you see a 604 SIP message back from IPVS then the device is not presenting the correct CLI to the
IPVS platform or the account is not present on the IPVS platform.
SIP Trunking DDI Users must have an active Public Number (DDI) on the IPVS Platform.
Legacy PBX users/extensions
(who do not have a SIP Trunking User account provisioned)
must present
the SIP Trunk Group number or ‘Bearer Number’ as their outbound CLI for calls to be able to traverse
the IPVS platform.