VoIP using LAN to LAN

I hope this FAQ will help with enquiries about setting two sites for VoIP. The link could be xDSL, lease lines or even Frame Relay controlled by third party routers. It does not matter, as long as you could ping from one network to another, and that the third party routers support the protocols that you are using. Other configuration with the WAN ports are possible.

I do not intend to rewrite the manual, but if my information is wrong, please do correct me. Please note I have several fully functional sites with this similar setup.

Required hardware:
IP Office or ArgentBranch at both sites
VCM at both sites.
Static IP Address for ADSL modems.

You will have to use your imaginations:


Site A Site B

ADSL Modem ADSL Modem
192.168.42.254 /24 172.16.0.254 /24

___ ___
| | xDSL | |
--| |---/-------------------/---| |---
| I__I I__I |
| |
| |
| |
| ____ ___ |
| | | | | |
| | I | | I | |
I_| P | | P |_|
| O | | O |
I___I I___I

IP Office IP Office
192.168.42.253 /24 172.16.0.253 /24

Extn range = 200 Extn range = 300

Line;
Line Group ID = 20 15
No of channesl = 5 5
IP Add = 172.16.0.253 192.168.42.253
Compression = G.729 G.729

Short Codes;
Short Code = 3N 2N
Telephone No. = . .
Line Group ID = 20 15
Feature = Dial Dial

IP Route;
IP Address = 172.16.0.0 192.168.42.0
IP Mask = 255.255.255.0 255.255.255.0
Gateway = 192.168.42.254 172.16.0.254
Destination = LAN1 LAN1