Vonage install problems w/ RT31P2 and D-Link DCM 200

Posts: 4

I just found this board and am hoping that someone else has had the same problem I am having and has been able to fix it.

I am attempting a simple install of a Linksys RT31P2 router for Vonage. I am plugging the ethernet cable from my cable modem into the internet slot of the router and then plugging another cable from port 1 into my ethernet card on the PC.

When I run the setup disk it gets to the point where it tests the internet connection and then it comes back and says it cannot communicate w/ the cable modem and to reset the cable modem. I tried this repeatedly and then called Linksys. After 2 hours w/ two different guys in India they said it's defective and to return it to Vonage. I called Vonage and went through the same drill and they sent me a new one. I received that today and am getting the exact same error message.

Has anyone else run into this problem w/ this hardware config? Thank you in advance for any help you can offer.

Posts: 646

I've got the same router, same modem, same problem. There seems to be some kind of electrical problem with the DCM-200 that prevents it from talking correctly to the RT31P2. I found a couple ways of fixing it that you may want to try.

First, try putting a hub or a switch in between the router and the modem.

If you don't want to have any bulky hardware in the mix, then try this: Connect a 33pF capacitor between the green and green/white wires of the patch cable. I'm not really sure why it works, but it worked for me. I don't know if 33pF is the optimal value to use, but it was the smallest one I had around.

I posted a bit more about this in a previous thread:
http://www.vonage-forum.com/ftopic1951.html

Let me know if you need me to be more specific about anything.

Posts: 4 · Posted: Wed Dec 29, 2004 11:08 am Post subject: Next......

Either I'm a real rock (a very good chance) or something else isn't kosher. I went out and purchased a Linksys EZXS55W 5 port Workgroup switch and set it up. I can't even get connected to the internet through the switch. The instructions that came w/ the switch are a joke, but I'm assuming that the cable coming from the back of the cable modem would go into the "uplink" port and a cable would go from an open port to the ethernet card of the PC.

Please let me know exactly which cables go where so I can at least check to see if that isn't the problem. I'm an electronics novice so I have no idea how I would make a patch cable Sad

Posts: 4 · Posted: Wed Dec 29, 2004 11:53 am Post subject: Followup

OK---I got all the wiring figured out, but I'm still not getting an internet connection through the router. I'm off to a co workers house who has the same modem to see if the problem repeats itself.

Posts: 646 · Posted: Wed Dec 29, 2004 1:13 pm Post subject:

Connect the uplink port of the switch to the network port on the cable modem. Then connect one of the normal ports on the switch to the "Internet" port of the RT31P2.

So, instead of going directly from the cable modem to the router, you have the switch in the middle.

Posts: 4 · Posted: Wed Dec 29, 2004 3:50 pm Post subject: Possible cause

The more I dink with this the more I'm convinced that the problem is with my cable modem vs the router. I tried to install a Netgear MR814v2 wireless router a couple of months ago and ran into the same problem that I'm encountering w/ the Linksys.

In both cases the router and modem aren't communicating and the internet lite flickers but never goes solid. If it's just the cable modem than all is well, but as soon as either router is introduced than zip.

The router is unable to acquire a IP address and reports it back as 0.0.0.0

I have a friend who has both a Motorola and a Toshiba cable modem so I'm going to try to install it at his place tonight to see if I run into the same problem.

Posts: 646 · Posted: Wed Dec 29, 2004 5:10 pm Post subject:

I agree. I suspect that the DCM-200 was designed with a flaky ethernet port, and something electrically just doesn't click with certain devices. However, if you can the cable modem to connect to your switch (via the switch's uplink port), then you should be able to make it work without getting a different modem.

Cable Modem <-> Switch <-> Router

In that setup, the switch acts like a normal cable, except that it regenerates the signals, allowing the modem and router to communicate.

However, it's possible that the problem could affect some switches as well. I tried successfully with a Belkin and a Siemens.