-------- Original Message --------
Subject: Contention or ISP or something else?
Date: Fri, 10 Nov 2006 08:44:59 +0000
From: The Invisible Man <nospam@nospam.com>
Reply-To: Please reply to Group
Newsgroups: uk.telecom.broadband


Hello

I seem to recall seeing here a way of identifying whether speed problems
relate to contention or to the ISP. Can anyone help?

I have an 8mb max connection with VISPA who remain very reliable for
getting on line at any time. Download speeds are varying between 1mb and
6mb download and 0.3 - 0.4 upload. Typically download under 4mb but just
recorded 5.5mb. (ADSL speed test)

BT comes up with the following. I am only 70 metres from the exchange.
My router is at present on the end of a 40 feet long extension but that
wouldn't explain the wide variations in speed.

http://speedtester.bt.com/ results as follows.

Results Image not loaded

Test1 comprises of Best Effort Test:
IP profile for your line is - 7150 kbps
DSL connection rate: 448 kbps(UP-STREAM) 8128 kbps(DOWN-STREAM)
Actual IP throughput achieved during the test was - 2504 kbps

TIA for any help.
-----------------------------------------------


Thanks to the person who replied to my original post above.

Part of the text of an email I have sent to my ISP is quoted below.

Hello

No response on this ticket yet.

Test results direct to speedtest@speedtest_domain give download @6,475kbps

A few minutes later ADSLguide via VISPA get my more typical 2,028 kbps.

Can you please explain why this might be please?

Thanks
Hugh

................................

The speed test has completed on test server speedtester1.nat.bt.com for
user 01245xxxxxx and you have downloaded a 1.7Mb file at a speed of

6475 kilo bits per second (Kbps), your service bandwidth will have
been quoted to you in kilo bits per second.

Your IP address is 217.47.66.153, your browser is reported as being
Microsoft Internet Explorer 7.0 and is running on Windows XP.

You may now disconnect from the speed test account (click 'disconnect'
in your internet connection window) and if you wish to regain normal
access to the internet please re-connect to your ISP using your usual
username and password.

Please note that test results may vary according to varying traffic in
the network. If you continue to experience slower throughput when logged
in to your ISP, this may be due to a slow internet site or high traffic
levels beyond the BT Wholesale Network. Please report this situation to
your ISP's helpdesk.



Speed Test Results
Downstream 2,028.7 Kbps ( = 2.0 Mbps ) Upstream 363.6 Kbps ( = 0.4 Mbps )

"The Invisible Man" <nospam@nospam.com> wrote in message
news:41e89$45547ca9$53d9a79a$26289@news.vispa.com. ..

The Invisible Man wrote:
One way which will probably work [1] is to ping somewhere while you
download.

If your pings stay low yet you have low speeds it's likely to be the ISP
, if they are high then it's likely exchange contention.

1. Bases on the assumption that your ISP doesn't shape by buffering as
most shaping kit/overloaded central will just drop rather than delay
packets (policing). Also it will be easier to see if you don't use tcp
window scaling (default is off on windows) as at 2meg speeds BT BRAS
buffer is big enough to hold >64kB.

Andy.