User`s manual

SIP User's Manual 8. Telephony Capabilities
Version 5.0 221 October 2006
8.10 Trunk to Trunk Routing Example
This example describes two AudioCodes gateways, each interface with the PSTN through
four E1 spans. Gateway ‘A’ is configured to route all incoming TelÆIP calls to gateway ‘B’.
Gateway ‘B’ generates calls to PSTN on the same E1 Trunk as the call was originally
received (in gateway ‘A’).
 Gateway ‘A’ IP address is 192.168.3.50
 Gateway ‘B’ IP address is 192.168.3.51
Ini File Parameters of Gateways ‘A’ and ‘B’:
1. Define, for both gateways, four trunk groups; each with 30 B-channels:
• TrunkGroup_1 = 0/1-31,1000
• TrunkGroup_2 = 1/1-31,2000
• TrunkGroup_3 = 2/1-31,3000
• TrunkGroup_4 = 3/1-31,4000
2. In gateway ‘A’, add the originating Trunk Group ID, as a prefix, to the destination
number, for TelÆIP calls:
AddTrunkGroupAsPrefix=1
3. In gateway ‘A’, route all incoming PSTN calls, starting with the prefixes 1, 2, 3 and 4,
to gateway’s ‘B’ IP address:
• Prefix = 1, 192.168.3.51
• Prefix = 2, 192.168.3.51
• Prefix = 3, 192.168.3.51
• Prefix = 4, 192.168.3.51
Note: It is also possible to define ‘Prefix = *,192.168.3.51’ instead of the four lines
above.
4. In gateway ‘B’, route IPÆPSTN calls to Trunk Group ID according to the first digit of
the called number:
• PSTNPrefix = 1,1
• PSTNPrefix = 2,2
• PSTNPrefix = 3,4
• PSTNPrefix = 4,4
5. In gateway ‘B’, remove the first digit from each IPÆPSTN number, before it is used in
an outgoing call:
NumberMapIP2Tel = *,1