i2004 static over VPN on cable.

[lewmar]

I have few i2004 telephones connected to BCMs via VPNs. Those using DSL work fine, those using cable have intermittent static and lose connection. Is it just coincident, or there is something special about cable connection. How to stabilize that connection?
I appreciate any help.

 

[gm85]

What type of connection do you have the BCM connected into?

There really isn't much difference between DSL and Cable when it comes to bandwidth, latency , jitter, etc. However, problem occurs when you have voice traffic trying to communicate between different ISPs.

The biggest problem with sending voice over the internet is that the internet is unpredictable and voice quality can not be guaranteed..... especially if it travels between more-than-one ISP. Although you may have two VPN endpoints in the same city (one on DSL, one on Cable), the traffic travelling between the two may have to travel a much larger distance and cross betwen multiple networks and ISPs before it reaches the destination (and all traffic on the internet is fair-game).

If your BCM is on a DSL connection and the clients are on cable, then this is most-likely the issue. Although voice-quality is not guaranteed on the internet (as I mentioned), usually the best option to minimize this issue is to have the BCM and the phones on the same ISP (such as all on cable from ISP A, or all on DSL from ISP B). This minimizes the distance and hops the voice data has to travel and in many cases means it can usually stay on the ISP's backbone and provide a good quality call.

If you are in a situation where you have areas that only have access to cable and other areas have access to DSL, many ISP's offer both technologies (for instance a cable ISP also might provide DSL.... if their company is large enough to support both). This usually provides the same benefits as above.

Other than that, it sounds like there may not be any other options. The breakups you are hearing are usually the result of jitter and usually that can't be fixed if it's travelling over the internet. Usually the biggest answer to having voice travel over the internet is to try to stick to one ISP for all your endpoints.

 

[lewmar]

Thank you gm95, this is probably it. We have BCMs always on DSL and only some phones on cable from different ISP. I will test it with DSL.Thank you again.