VoIP with remote sites

[rbergonzini]

I'm implementing VoIP environment with remote sites. I need to place some VoIP phones on externally site connected via WAN link with (or not) tunnel between headquarters and branch office.
LAN of headquarters is protected by firewall. All phones are configured as internally of 3CX PBX.

- Emulate external connection by VoIP phone directly attached to firewall WAN interface communication work fine.
- Remote VoIP phones sometimes fail registration to 3CX PBX.
- Remote VoIP phones sometimes can establish dialing to other internal phone but communication are dropped after 30 sec.

Thanks for all.

 

[Anonymous]

To do it wright you need VPN.

The 30 sec drop out is related to the SIP/VoIP registration, it cannot register due to NAT to solve that you can use STUN, but that only works good for VoIP to VoIP dialing not using extension dialing.

So VPN is your best bet.

3cx (company) does not support WAN extensions, but some of us have been able to get it to work. My take on this is, if it has an IP we should be able to get it to work.

Also make sure you have your Ports open for the SIP, RTP etc.

 

[deGuile]

I'm using the VPN method and it works very well. Easily installed in Windows server or winXP. One should be aware though, that any shared folder/drive if not password protected becomes browseable by the network, also , internet web browsing is then re-routed through the vpn server firewall. That means you are subject to the firewall rules of the remote vpn server site. So for a branch office it might be quite suitable. It's as if you're in the next office. The only ports on the firewall that have to be opened are tcp:1723 & protocol:GRE

Cheers
deGuile

 

[mujalli]

Please deGuile, could you post for us how to configure a VPN on winXP

thanks friend

 

[rbergonzini]

Tunnel (IPsec normally) mentioned for connection between headquarters and branch office is established for stealth porpose. So service is unvailable for other users. But if no VPN can be established NAT between 3CX PBX and remote phone can compromise connection?

 

[dekatech]

Works if using a Point to Point as well as VPN

Travis