UDP port 8000 problems

I play an MMO during which I get disconnected far more often than other people. Having browsed a few threads on this forum I started using RouterStats and I saw something which surprised me.

The noise margin trace is linked, and explained below
http://www.mediafire.com/?eqg99mn5bcbbwmg

Noise margin - what I was doing at the time
5 - I was browsing the web - connection speed was 1000 Kbit
4 - playing normally
2 - Connecting to the game and going through a door in the game
0 - lost internet completly whilst trying to go through a door in game

7 - Internet restarted at a lower connection speed, 800 Kbit

So my noise margin drops considerably when I am going through a door in the game.
Investgating a bit I discover that going through door (and Connecting to the game) uses UDP port 8000, whereas normal play, or internet browsing uses something else.

Is it normal for my noise margin to depend upon what i am doing, which port I am using?

My ISP is Sky and exchange is Brimscome
http://www.samknows.com/broadband/exchange/SSBRI


Leting RouterStats run a bit more I see a lot of dips in my noise margin
http://www.mediafire.com/i/?5t29ncg8ok6962z

I hesitate to say it but I would suspect it is pure coincidence. The noise margin is a physical property of the line that I cannot imagine has any way to be affected by the port that a bit of data is using - the port has no impact on the physical characteristics.

The only reason I say I hesitate to say it is that I am not fully versed in quantum physics and metaphysical doorways or indeed in the workings of any supreme being However, if I stuck my neck on the line I would put money on the two things being totally unconnected.

Quite a big coincidence, I went through 4 doors in the game and each one resulted in a downward spike,
Of course it is not just the port number that changed, there would be a burst of internet activity associated whith each change, which I imagine had more effect.

In reply to a post by zzCoins:

Is it normal for my noise margin to depend upon what i am doing, which port I am using?

No.

Leting RouterStats run a bit more I see a lot of dips in my noise margin
http://www.mediafire.com/i/?5t29ncg8ok6962z

More likely something electrical was turned on or off in your house, or a neighbours. There might be a possible fault in your BT phone wiring.

It may be that going through a door results in a burst of UDP traffic whcih creates issues for the NAT part of your router, and thus it crashes and resyncs

UDP or TCP should be independent of the ATM layer the ADSL runs across.

In reply to a post by MrSaffron:

It may be that going through a door results in a burst of UDP traffic whcih creates issues for the NAT part of your router, and thus it crashes and resyncs

I do not think the problem is my end. This has been going on for 6+ months, my connection is good for 3-6 weeks then changes to bad over the course of 1 week.

The last 2 times that my connection has become good again have been immediatly after a power cut affecting the neighbourhood, turning off my router overnight makes no difference. This might be a coincidence as it has only happened twice.
My theory was that my local exchange was slightly overloaded, and was restricting my service to give reduced UDP traffic. A power cut would reduce the load on the exchange so it would reset to offer full performance. then a few weeks later it would change mode again to only allow a reduced service. Is this possible?
I would expect an exchange to react to being overloaded a lot faster my original theory.
When I saw my noise margin graph I started by asking about that.


Normally I only play the MMO in the evenings, this morning my noise ratio is 6 with hardly any down spikes and no problems in game. So it definitly looks like a capacity problem, rather than dodgy hardware at my end

Edited by zzCoins (Sat 13-Nov-10 14:19:21)