sarah_orange: (Default)
Sarah McCormick ([personal profile] sarah_orange) wrote2010-05-26 11:38 am

Calling all Network Wizards!

the FOC house is (still) experiencing network issues. I say network issues because I don't think there's anything wrong with the Virgin connection. Most of the time we're getting our correct download and upload speeds (although I shall do some checks over the next few days and add them to the post just for completeness) and more importantly it's possible to recreate the problem.

the problem is with torrenting or peer to peer file stuff. After my last round of trying to sort stuff out I worked out that unplugging Al's pc from the network stopped the problem. After some discussion it transpired he generally had torrents going but had the download speed throttled. Headscratching. Turns out he didn't have the upload speed throttled. Breakthrough. Apart from it wasn't. The downloads and uploads are now throttledand the problem still occurs. So Al now has his torrents scheduled to run after we go to bed and during the day midweek.

I've taken to having a cmd window open most of the time pinging the bbc website on loop to keep an eye on response times. generally it'll be around 20-40ms - during one of the problem times it will be 1000-2000ms. Sometimes its a bit lower and I can play wow but get disconnected frequently. Last night it was slow - well over 1400 average but Al wasn't torrenting - so I rebooted some stuff and it turned out Fuzzy was - same thing though - download and upload were suitably throttled. So we thought we'd experiment a bit.

Firstly here's our set up - we have the virgin broadband modemy thing which has one output. that goes directly into the netgear modem they supplied. this does the dhcp and stuff. from this the wii and xbox are connected (but are generally switched off) and a line runs to the upstairs router. the upstairs one is the same make of netgear (but vx.x.7 where as downstairs is vx.x.9 I believe) - it has a fixed IP address and dhcp turned off. the range for dhcp on the downstairs router is set to start 1 higher than the IP of the upstairs one so there are no clashes with things in the house. we have the 2 routers as one router isn't enough ports and the signal from the downstairs one doesn't cover our tall victorian house. originally we had just the new router upstairs and still had this problem so it may not be specifically related to the second router. I've downloaded wireshark but frankly that shit baffles me...

anyhoo. as an experiment last night fuzzy took his pc downstairs to see if starting his torrent down there had the same effect as from the upstairs router. it did. interestingly when he started the torrent up his ping stayed ok for a minute or so before gradually getting worse. this made me think that my idea that the problem may be somehow connected to broadcast storms or something had some validity. as another check I made sure that all the pcs in the house were experiencing the latency - not just mine.

so there you have it - I'm going to have a look through both routers tonight and add the settings onto this entry as I forgot to write them down last night (hey al was out and fuzzy stopped torrenting so I got to enjoy 20-40ms latency on WoW which, suprisingly, doesn't appear to increase the ping times by any noticable amount (maybe it's increasing it to 25-45 but that's it...)) I've also noticed that WoW patch updates cause the problem too (as they are torrented peer to peer) and it took me nearly an hour longer to install one than D the other night :(

anyone that could provide us with suggestions and tips and explainations will be rewarded by much gratitude!
there may even be boozes in it ;)

feel free to comment anonymously if you're not on LJ - it'll screen it but I can relase them - put your name on so I know who to squee at :D

[identity profile] steer.livejournal.com 2010-05-26 11:02 am (UTC)(link)
This is usually caused by the asymettry of ADSL. The upload bandwidth is much less than the download bandwidth so you need very aggressive upload throttling or a huge outgoing queue builds. Also you will find that some torrent clients don't implement upload throttling properly and you will also find that some autospeed algorithms fuck things up in exactly the way you describe.

My suggestion is to try P2P with real heavy upload throttling on -- like measure your upload bandwidth using a speed test site and then throttle to 20% of that or less. Don't use P2P autospeed algorithms as most work by saturating the upload link.

[identity profile] glennkenobi.livejournal.com 2010-05-26 11:19 am (UTC)(link)
I never knew that downloading porn could be so complicated :-D :-)

[identity profile] urbancannibal.livejournal.com 2010-05-26 11:32 am (UTC)(link)
My suggestion is to give up playing WoW and choose a proper MMOG instead. :P

[identity profile] http://users.livejournal.com/_pyromancer_/ 2010-05-26 11:42 am (UTC)(link)
Don't use torrents or P2P.

What's probably happening is Virgin's deep-packet inspection stuff is spotting that your connection is doing P2P type stuff and throttling your connection all the way back as a result. It's not a fault, it's deliberate bandwidth throttling, partly in response to music / movie industry pressure, and partly simply to protect the Virgin network from traffic saturation.

I'd suggest, if people are determined to use P2P or Bit Torrent, you want two separate connections, the Virgin cable one for legitimate stuff, WOW, normal Internet browsing, legal downloads from Amazon, etc, and a separate phone-based ADSL connection, preferably from a small local ISP (who are less likely to be doing aggressive automated deep-packet traffic profiling), for all the dodgy stuff. And make sure people use the correct connection for the traffic they want to run.

If I was doing it I'd have two seperate wired networks, and tell people to plug in to whichever one they need - use green cables for the legit one and red for the other, so it's easy to keep track of. But then I simply don't trust wireless connections.

Actually, thinking about it, use wired for the legit and wireless for the other. Gives a better get-out clause if anyone ever comes knocking, "someone external must have broken our WEP key".

[identity profile] bitwise-bob.livejournal.com 2010-05-26 11:59 am (UTC)(link)
Could be an issue with whichever router connects you to the internet.
Presumably it will be running NAT ( using 1 internet/public IP address for all your internal machines), if it is then it has to keep track of every connection between your LAN and the internet - with torrents running that could be thousands of entries in its table to process -- some routers just aren't up to the task.

If this is the cause you'd probably see the problem continue for a short while after the torrents were stopped (until the router ages the connections out of its table)

There may be a new firmware for the router, always worth a try.

[identity profile] thatmakesmemad.livejournal.com 2010-05-26 12:08 pm (UTC)(link)
Limit the number of simultaneous connections on the bittorrent clients ?
Virgin apparently have application management so prioritize different applications for traffic access (http://www.virgin.net/allyours/faqs/trafficManagementFAQ.html) but then since games are the highest this doesn't explain the drop outs.
I seem to remember that earlier models of netgear routers had problems with excessive numbers of connections causing them to keel over.
What model of netgear router is it ?

[identity profile] axy-666.livejournal.com 2010-05-26 01:38 pm (UTC)(link)
I think it's all been said above however here goes:

From what I remember from Virgin they will throttle at peak times if your connection is getting hammered. I think it's like 2Gb in an hour or a little less before your connection gets throttled. I've not looked at the AUP thing but it was something that happened to me on Virgin when I was still in the UK, I cursed them for it too.

If you are getting drops with a fair few users I would also say take a look at the Router connected to the Virgin modem. Personally, if you have a lot of traffic going through a cheap-ish Netgear expect the drops, I think I have the same one running the wireless here and that's about all it's good for imo.

I'd recommend something that's actually built to handle high traffic. For example I have a cable connection over here in Ireland, I'm using a Draytek Vigor2100V (it's a wired voip router), I had that on Virgin over in the UK too and all I can say is the connection was rock solid and is over here in Ireland on UPC cable. So I'd be looking to spend out and get a decent router, such as a Draytek SoHo router, too.

[identity profile] bitwise-bob.livejournal.com 2010-05-27 05:35 pm (UTC)(link)
Some torrent clients will allow you to limit the maximum number of peers/connections (globally or per torrent) independently of the bandwidth allocated. If possible scale it back a bit & see if that helps any.