Speed issues, please check my line stats, etc.

[GSDog]

Hi all,

I have been with BT MaxDSL for about 8 months now. It has been connected at roughly 7-8MB, but the actual download speeds rarely goes over 350kbps, and after doing speed tests I have never seen the connection speed go over 3.5MB.

Here are my line stat's:

What do you think could be causing this? I know some speed will be lost from the exchange, but surely not over 50% of the connection speed?

 

[GSDog]

This computer is on wireless, but the other PC is wired. I used these speed tests:
http://www.speedtest.net/
http://www.thinkbroadband.com/speedtest.html

The connection has been stable, I think it has only dropped once, which was actually last week, but it reconnected after about an hour.


The BT speed test link does not seem to be working for me...?

I have been on this for about 8 months and it has never gone over 350-400kbps when downloading - even when it is connected at the full 8MB.

I just ran another speed test and it never went over 2MB!

 

[GSDog]

You SNR (Downstream margin) seems low it should be 6db or higher, this could mean the router is dropping the line every now and then, are you sure its only done it once? Might be an idea to look in the Log

If not fair enough, the download limit could either be at the exchange end or on the ISP's system so might be an idea to call your ISP

Also one other thing to note, do you online game much? Just asking at interleaving is on which isnt bad as it stabilises your line however adds to you latency (20-40ms) and so games can seem jumpy more

the bt speedtest hasnt work properly for me for the last 3 months!

Thanks for the reply.

It's strange because the SNR is usually around 6-8, not sure why it was 2 last night, but right now it is back up to 7db...

I did try calling my ISP once about this, but they are absolutely hopeless - they said everyone with 8MB MaxDSL will not actually get 8MB - I said I knew that, but I was connected at 8MB, so should get at least 5-6MB+, surely?

I do quite a bit of online gaming and I know Interleaving does effect my pings (they are around 40ms) but I don't notice any lag. I will ask them to turn it off tho.

My router is not plugged into the master socket because we still have one computer on a wired network upstair's - do you think it would make a different moving the router to the master socket?
I think the master socket is very old and I remember thinking about using a different faceplate.

I guess I might as well try phoning BT later on.

P.S) Even though the SNR is back up to 8 now, the download speeds are still not going over 3.5MB.

 

[GSDog]

BT wont do nowt unless thats your ISP

Have you tried the BT speed tester again? I ask as this will tell you your IP/BRAS Profile (ie 3500kb) and so will tell you if the exchange is limiting your speed, other that that phone your ISP ask for your IP/BRAS Profile as it could have got stuck!

Moving your router might mean you get slightly better figures but it wouldn't affect the lack of bandwidth

I have tried that BT speed tester link on all 3 computers, it isn't working and just times out.

My ISP is BT, so they should be able to tell me.

I have just used this speed test: http://www.btopenworld.com/speedtest and downloaded the large file. On my computer it downloaded between 400-430kbps, which is MUCH better than last night, when it was barely hitting 200kbps.
However, I just tried this on the other two computers, the family PC (which is wired) is always between 600-700kbps!!! and my brothers PC (which is wireless) was hitting 750kbps!!!!

So it looks like it could actually be my PC
It's weird because I think I remember this happening last time on my old desktop PC (im now using a laptop), my download speeds in my room never seem to be as fast as the other computers.
What could be the cause of this???
I have tried IE and Firefox, they are both around 400kbps on this PC.

 

[GSDog]

As the other machines are getting good speeds then it is defiantely going to be a setting on your machine.

What OS is it running ?

You might need to tweak the Rwin value if you run the TCP Analyzer on the following site and post the results will help

http://www.speedguide.net/sg_tools.php

It's running Windows XP Media Center Edition.

Here are the results from the TCP Analyzer:
« SpeedGuide.net TCP Analyzer Results »
Tested on: 02.20.2007 06:25
IP address: 86.138.xxx.xxx

TCP options string: 020405ac0103030001010402
MSS: 1452
MTU: 1492
TCP Window: 17424 (multiple of MSS)
RWIN Scaling: 0
Unscaled RWIN : 17424
Reccomended RWINs: 63888, 127776, 255552, 511104
BDP limit (200ms): 697kbps (87KBytes/s)
BDP limit (500ms): 279kbps (35KBytes/s)
MTU Discovery: ON
TTL: 108
Timestamps: OFF
SACKs: ON
IP ToS: 00000000 (0)

It does say at the top:
MTU = 1492
MTU is optimized for PPoE DSL broadband. If not, consider raising MTU to 1500 for optimal throughput.
MSS = 1452
MSS is optimized for PPPoE DSL broadband. If not, consider raising your MTU value.

I am using PPPoA, so could this be the problem?

 

[GSDog]

Thanks.

I have now changed the Rwin to 255552.

I just checked my line stats and my SNR is back down to 2db. I have just downloaded the BT Openworld speed test file again, and all 3 computers are barely getting over 250kbps.

It seems my SNR drops every night - I can almost guarantee that tomorrow morning the SNR will be back up to 7-8 and my speeds will be back to normal.

I guess I will need to wait and see if the Rwin has made a difference tomorrow!

 

[GSDog]

We don't have street lights were I live, but I will check tonight when the heating or any lights come on.

Well, just as I guess the SNR is back up to 8db this morning/early afternoon. I will keep an eye on it and see what time it starts to drop.

The good news it, I just tested the BT Openworld speed test again and it dowloaded at 680kbps!!! That is the fastest I have seen it download on this computer, so fingers crossed it looks like it was the Rwin causing the slow speeds on this computer.

Thank you very much HomerJ for sorting that out.
And thank you ste_bla for your help too, hopefully I will find out why the SNR drops so much at night.

 

[GSDog]

So what is the purpose of interleaving?
I do online game quite a bit at the moment and have noticed my pings have increased, so I will probably phone BT later and ask them to switch it off.
I have noticed today my connection is now syncing at 7232 Kbps instead of 7902 Kbps.
I'm not too bothered because the SNR has now increased to a healthy 10db. Hopefully tonight it wont drop as low as recently.