D-Link VTA question: no port forwarding needed?

Posts: 7 · New Forum Member Joined: Mar 09, 2007 Posts: 7

I got my D-Link VTA last Friday, and we're very happy with the experience so far. We make a lot of calls between US and UK, so I'm looking forward to saying 'bye to the Verizon and AT&T bills.

I have Comcast and an original-edition Microsoft wireless router (MN-100) which still works just fine for me. I just plugged the VTA into an Ethernet socket and it just worked, two-way voice, incoming calls, no problem. I can stream video with no impact on quality, and I don't run any outbound services on the PC.

So now I wonder why I didn't have to forward ports 10000 and up on the router. Does the VTA hold an outbound connection open all the time, so that it can receive calls as well as make them?

Posts: 4777 · Vonage Forum **MVM** Joined: Aug 30, 2005 Posts: 4777

I'm not a networking guru, but port forwarding is normally not required with Vonage. The Vonage adapters do "call home" periodically, maintaining contact with the Vonage servers.

Posts: 3 · New Forum Member Joined: Mar 10, 2007 Posts: 3

Thats what I first thought. I also have VTA adapter and been with Vonage for almost 3 weeks and I would say quite satisfied. If im not a techi I wouldn't mess with my VTA adapter.

I have a Netgear router WGT624 and Roadrunner for my internet connection (5MB download 2.5 upload speed),behind my router is my VTA. The first thing I've noticed after I installed it was after I dialed a number and it goes to ring.. the first ring would be garbled and after which its fine.

First I was surprised I didn't have to do anything for the VTA .I thought "there's something wrong with that" so I decided to do a port forwarding. After that, After that the garbling went away almost instantly. After 2 weeks, when I checked my dial tone one day it keeps on beeping like its trying to connect to the router. I've power cycled all my equipment but to no luck its still the same, (it really wouldn't be a problem if I'm not that picky but I AM) lol. Found out that my IP has changed again (yeah, I've asked RR if they can give me a static IP, they said that they don't do that for residential customers) checked the port forwarding but no luck, its still the same (beeping dial tone). So what I did was put my VTA's IP to the DMZ server and problem went away.

Posts: 2257 · Posted: Sat Mar 10, 2007 8:19 am Post subject:

Whether you need port forwarding depends on your router. With a normally-functioning router, you do not need to port forward. You just need the ports open, and you can't really close ports on most consumer routers anyway.

However, there are two things that can go wrong with a router that will force you to port forward:

1. Your Vonage adapter sends out a signal every minute or so to keep a connection to the Vonage servers alive. When you get a call, Vonage is technically sending a reply to one of those keepalive signals. However, if your router closes the connection between keepalive signals, then Vonage has no way of sending the reply. This would be a ridiculously fast timeout, but if your router does this then you'd have to forward the ports.

2. Some routers come with "flood" protection, that detect large numbers of packets flooding in on a single TCP/IP port. The router will either throttle the connection (slow it down) or close it entirely. If your router has flood protection, you should turn it off, since some routers seem to think that Vonage is a flood attack. If you can't turn it off, putting the Vonage device in your DMZ can sometimes tell the router that it's OK if the machine in the DMZ gets flooded.

From what I've seen, NetGear routers have real problems with #2.

Some really old Vonage devices may use a different method for connection that requires ports to be forwarded, but I don't think so.

Posts: 143 · Vonage Forum Senior Joined: Dec 22, 2005 Posts: 143

If you have a router with a firewall that's the only time you need to forward ports.

The ports are udp:

10,000--20,000
and 5061

Posts: 4777 · Vonage Forum **MVM** Joined: Aug 30, 2005 Posts: 4777

Nate, you might want to add that little discussion to your online notes. Very helpful.

Posts: 533 · Posted: Mon Mar 12, 2007 9:02 am Post subject:

Trinijoy wrote:

If you have a router with a firewall that's the only time you need to forward ports.

The ports are udp:

10,000--20,000
and 5061

No, not true. You need no port forwarding with Vonage. As NateHoy already said, everything with Vonage is outbound from the adapter, port forwarding is only needed in cases when an outside source establishes a connection to you, which is not the case with Vonage.

Posts: 43 · Full Forum Member Joined: Dec 27, 2006 Posts: 43

I don't think 'everything from Vonage is outbound'; clearly when someone calls you then that is creating inbound rtp traffic-->inbound traffic that must pass through your router; if port forwarding were never an issue with Vonage why do we see it so prominently on portforward.com? -> because there are situations where providers or routers are using ports 5060 or 5061 or 23 or blocking them or whatever...etc; sometimes portforwarding may be necessary but it is not common, hasn't anyone here ever had someone at tech support done a dmz or port forwarding?... I'll bet 'yes'

Posts: 533 · Posted: Thu May 03, 2007 6:58 pm Post subject:

To be clear, everything is initiated from your Vonage ATA, those are the keywords, initiated from. A device blocking return traffic from the outside, such as a non-stateful firewall or a poorly designed firewall (read: residential grade) is completely different than the need to port forward.

Port forwarding allows for a NAT/PAT translation entry to be built using your ISP assigned public IP address and a private address inside your network, specifically for traffic initiated outside your network destined to you. For example, hosting a webserver on your internal, privately addressed, network that's behind a cable modem or DSL that has a public IP address assigned to it.

Configuring port forwarding on some devices may work around a design flaw or bug in the device that is preventing return traffic from getting back to you properly, but to say it is a necessary thing for Vonage to work is completely false.

Posts: 187 · Vonage Forum Master Joined: Feb 14, 2007 Posts: 187

a_van wrote:

The first thing I've noticed after I installed it was after I dialed a number and it goes to ring.. the first ring would be garbled and after which its fine.

Glad to hear I'm no alone (my post about this was probably just before you joined the forum).

I describe it as a "metallic chunk" and it's right at the end of the first ring. The ring starts out fine but ends strangely. Subsequent rings are OK.

My guess at this point is that it's a problem with [one of] the codex in the VTA.

Mark

PS - annoying but doesn't seen to cause any functional problems