sundance-communications.com/forum Forums TDM Business Telephone Systems Vodavi Telephones & Systems Vodavi VOIP & Time Warner Cable

Greetings All,

We have a client with 2 locations, with DVX plusII and 4-port VOIP boards on each end. Initally one end had Time Warner Cable for internet and the other end had Adelphia Cable. Everything was working fine. About 6 months ago TW bought out Adelphia and that is where the problems began. Shortly after the acquisition TW provided a new IP range for the legacy Adelphia client and we suddenly couldn't get VOIP connectivity. After much to do, TW agreed to go back to the old IP range and everything started working again. Well, last week TW finally mandated the change to new IP's and once again everything went down. We have now tried 2 different IP ranges and still no success. As a final resort, we're considering a VPN for voice traffic to see if that might help. Anybody run into a similar situation or have a suggestion??

Are you sure that you are using DVXplus systems?

We had a similar issue with a different cable provider but it was due to the fact that they could not put our sites on different subnets. They finally gave up and conceded that they can't give that to us. We ended up having to get DSL at the second location.

Thanks for your response Ed. Yup, definately DVX PlusII's. Why do you ask? Currenly both sites have separate subnets, IP Schemes, etc.
We've had great success with this application in the past, so am at loss for what the issue may be.

I ask because I was told by Vodavi's former director of technical support that the DVXplus series would not support VOIP several years ago. I just took his word for it. We have changed many of them out to XTSc's for this very reason.

When using the new IP range, are you able to ping both sites? If so, that pretty much proves that your VOIP is being blocked.

As much as I hate to say it, it's pretty obvious that this is a TW issue. Getting them to acknowledge it is another story.

Well, my techs are on the road to set up a VPN for their voice traffic. Don't know if it's going to work, but will definately report back.

Regarding the DVX Plus, we've got several clients running VOIP over DVX PlusII's - In fact, my senior tech prefers them to the XTSc for this application.

Ed,

OK, I think I understand your previous statement. The DVX plusII won't support VOIP endpoints, but it will support VOIP networking, which is what we're doing here. Sorry, I should have been clearer.

No need to apologize. That makes more sense now.

Ed,

Wanted to close the loop with you (and anybody else who was tracking this). We installed a VPN using 2 x Netgear ProSafe VPN Routers and the voice connection came on line immediately. I'm still bewildered as to the cause of this issue, as we've got several other clients networking through VOIP over Time Warner with no problems at all. Thanks again for your help.

I don't get what is the problem here. If both the ip addresses of both sites allow internet access why is a VPN needed? I have sites that share the same subnet mask and they are working fine. The only problem I have had (other than not enough bandwidth) is at one new install the address assigned by the provider was also the gateway for the other site on the same subnet. So when I brought the new site up...it knocked the other site down. That of course led to lots of time on the phone with Cox's tech service people.

Derrick,

I wish I knew. We tried multiple IP schemes on both ends, all to no avail. The VPN was a last ditch (and a complete shot in the dark) effort and it seems to have worked. I've got to believe this is a network issue with Time Warner - Somehow their existing network isn't synchronizing with the legacy Adelphia network. This is only a guess, but the only thing that makes sense. Old Adelphia IP's work fine, new TW IP's don't. I'm not a VPN expert by any means, but my understanding is that by "managing" the connection with a VPN it alters the voice packets just enough to get through. If there is someone out there who could add some clarity I'd be happy to listen.