VPN between sites

[simonchunk]

I have been using 3CX for a few months and have great success, however we struggle with communication to our other site.

The current config that we use is:

Local LAN in our main site (A), all phones talk without issue.

Site (B) has a VPN to our internal LAN at (A). The extensions are simply routed to (B) like they are part of the LAN.

The issue we have is the call quality is choppy at times and constantly looses voice. If (B) calls (A), it won't connect on first go, but will on the second time. If (A) calls (B) it will connect everytime, but sound quality is low and drops out at random times.

What we are trying to acheive is simply communication between our employees, nothing more. I do not need to talk to external lines, etc, just office communication. We have decent DSL in both locations.

Any tips would be greatly appreciated.

 

[leejor]

Have you tried running an extension, from the remote site, NOT over VPN as a test? Depending on what type of VPN you are using, it may be introducing enough latency to be noticeable. Whereas data can tolerate latency, or even dropped packets (as the can be re-sent), voice can , only up to a point, without it being noticed.

You may want to speak to whoever set-up/installed your network to see if there are issues to be corrected, or , at the very least, do some testing to pinpoint the cause. There may be a switch, or other hardware causing a bottleneck. In some cases, changing the Codec settings can help.

If (B) calls (A), it won't connect on first go, but will on the second time. If (A) calls (B) it will connect everytime, but sound quality is low and drops out at random times.

The fact that calls do not go through at times may be an indication of other issues. You should be looking at the 3CX Server Log after one of these call failures to see what happened.

 

[simonchunk]

Ok, have been doing a bit more digging and I think I might be onto something.

If I follow this guide and set the other office up as a remote extension, then I should be able to talk fine?
http://www.3cx.com/blog/docs/provisioning-a-remote-extension/

Does that sound like what I need?

All I want is the offices to talk internally.

I have multiple PC's available to be 3CX phone systems if needed. I have DSL connections at both sites and the ability to port forward, etc. Do I need anything else?

 

[leejor]

If you have a remote site with one or two extensions, and VPN is not really required, then you may have better results simply running the sets outside the VPN.

If you have a site with a number of sets, then you may want to consider running the 3CX Proxy server at the remote end.

http://www.3cx.com/blog/releases/sip-proxy-manager/

 

[simonchunk]

Great, I'll see how I go. Thanks for the information.