Connection disruption

[sanders]

I have been using Wingate without issue for some time in a simple NAT configuation for sharing a broadband internet connection at home.

Recently, I have begun to use VOIP a lot after I upgraded to Wingate 6 and bought faster broadband.

This works perfectly, although I have observed that if a new client joins the network, the connection to the other clients is momentarily disrupted. For the most part, this is not a problem. If the clients already on the network are simply browsing the web, then a short break in the connection would go un-noticed. However, with a VOIP stream, this is sufficient to cause complete disconnection. If I'm calling a land-line, this can be hard to explain to the person I have just hung up on!

Can you suggest any reasons why this might be happening and propose any solutions?

Many thanks.

[Pascal]

Do you by any chance use a wifi link?

[sanders]

Apologies for the delay in replying!

Yes - I do have a wifi link.

I have a Belkin Wireless Access Point (model number F5D 6130) installed on the server that shares the internet connection.

Hope this sheds some light on the problem!

[Pascal]

Okay, this is going to sound a little bit crazy but I had the same problem at home. Was a bit annoying when playing Guild Wars as the connection would drop randomly.

I'd recently put in a wireless link and needed to reshuffle the hardware a bit to get the ADSL -> AP link close to a phone line. In the process the WiFi access point ended up about 1m from the microwave. (Only phone plug available was in the kitchen :) ) Moving the wifi link away from that helped, boosted signal strength from 30% to 98% and suddenly gave me 100% 802.11g throughput.

That is not the only device that can cause problems for wifi links - cordless telephones. They operate in the same 2.4ghz band (Usually). What you can do is check with the application / driver set provided with the wifi link what the signal strength is like. If that is very low then you might need to investigate that as well.

If nothing seems wrong there, then we might need to look at a packet capture on the WG Server to get an idea of where / what terminates connection.

Regards,

[sanders]

Fortuately, I have been able to locate my WG server outside of the kitchen and away from the microwave!!

However, the wireless access point is right next to our cordless phone.

When I first bought the access point, I was getting the same problems as you. The signal was very erratic and at times dropped to almost 0%, causing disconnection. The first thing I checked was the phone. I thought I had ruled that out because it was working on a different frequency to the phone (I can't recall which but I can find out if you want to know) and the problems with the access point signal persisted even when I unplugged the phone from the mains. Strangely, installing XP SP2 on the client laptop that uses the access point seemed to cure that problem.

So I will look at that again, as I still get the signal problem at times, however...

...I have the problem I described in my first post over a wired network link. In other words: if I am using VOIP on the PC upstairs, connected to the WG server with a wired link, and another client joins the network with a wired connection, then the link to my PC using VOIP is disrupted slightly, breaking the call.

I look forward to your thoughts!

[Pascal]

Hehe. Okay, so not that then. I also found that XP SP2 had a significant improvement in wifi stability over SP1 / barebones. Couldn't get the wife's machine up and running without patching it to SP2.

Anyway, moving onto the VOIP / wired link then. The easiest way to diagnose this would be to isolate where the connection disruption is coming from as WinGate should not disconnect any connections when a new machine signs in.

Firstly, how do your machines connect through WinGate? It sounds like simple NAT... but want to confirm that. If so - can you reproduce this easily? If so, would it be possible to do a packet capture on the WinGate Server capturing the VOIP comms?

You might need to use an application like ComView / NetPatrol / other to watch the traffic first to isolate which ports are in use and to then capture the actual stream. What we're looking for is the connection closure (If there) to see who / what side of the connection closed it.

[sanders]

The client PCs do connect to the WG server in a simple NAT configuration. The server is not working as a proxy server or anything like that. WG is working more or less "out of the box", as it were.

I will look into finding an application such as the two you have suggested and then attempt make the capture/s you mention.

It might take me a day or two to replicate the problem and capture the results. I'll try and do it over the up-coming weekend.

I have not done a port capture before, but I assume I will be able to export the results into some sort of file that I can send to you?

Thanks again.

[Pascal]

NetPatrol is available from the Qbik website. (30 day trial, so you can do the packet capture). And yes, the output can be saved to a file which you can then email to me.