worth checking at http://www.speedguide.net/analyzer.php or other tweak sites that your TCP/IP receive window or RWIN value is 64k or bigger. Small values can constrain data throughput.

You will have to persevere with the BT speedtester to find out your IP Profile, try early in the morning.

I think an analogy would be useful here.

You own a car that will go at a maximum speed of 100 mph. There are two things that can slow you down, a speed limit and traffic congestion. If the speed limit is 30mph it does not matter how fast your car will go, you are limited to 30mph. If the road is a motorway with a speed limit of 70mph but it is very congested - you may still only be able to go 30mph.

Maximum speed of 100 mph = your sync speed, say 6 mb/s
Speed limit = BRAS profile
Traffic congestion = Exchange contention

BRAS profile
You cannot download faster than your BT imposed "IP Profile", sometimes called your BRAS profile after the bit of equipment in the exchange that does the profiling.

Even though your router is synced at 6 mb/s the BT exchange equipment will always set your BRAS profile at a marginally lower figure. At 6 mb/s the BRAS profile will be around 5.5 mb/s and may be lower. If you do a speed test it will never show a result higher than your profile.

The BRAS profile is based on the lowest speed at which your router synchronised in the past 3 days. So although it may happily sync at 6 mb/s at the moment if at any time in the last 3 days it synched at (for instance) 2 mb/s then the BRAS profile will be set at about 1.5mb/s. The BRAS profile resets after 3 days, so if your router holds sync at 6mb/s for three days then it will reset your BRAS profile to around 5.5 mb/s.

Exchange Contention
Broadband is a shared resource. In simple terms, the more people there are on your exchange trying to connect, the slower your speed tests will be. Almost everyone has slow speeds in the evening. My router syncs at 8 mb/s and my BRAS is 7 mb/s but between 6pm and 11pm my speed tests vary between 2mb/s and 4mb/s. At 1am I can do speedtests at over 6.5mb/s (in other words when no-one else is using the internet I get the road to myself!). There is nothing you can do about this, it is down to how well BT equip their exchanges.

Fiddling with group policies, MTU, Rwin etc will make almost no difference to your download speed if your exchange is heavily contended or if your BRAS profile is set at a low figure.

If you cannot get the BT speedtester to show you your IP profile, do this speed test http://www.speedtest.bbmax.co.uk/ at 2:00 in the morning. This will be pretty close to your BRAS limit. If this is 5mb/s or higher and you still get slow speeds in the evening then I am afraid it is all down to BT exchange contention.

There are problems that can occur with the BT equipment such as "stuck" profiles so post back if your system does not sort itself out.

Speed test results in

Seem to be getting a bit of a lift on the line, seems that a moan in the ear of UTV worked so-far, but as far as I can make out from the speed test there may be room for improvement. but hopefully this will happen over the next few days.

Thanks to all who helped me on this.
The speedguide tester said my router was not set up properly, is there a utility or programme that can set this up? or do I have to figure it all out myself?

BT Speedtester - at 22:40hrs on 10th October '06

Results Image not loaded

Test1 comprises of Best Effort Test:
IP profile for your line is - 4000 kbps
DSL connection rate: 448 kbps(UP-STREAM) 6720 kbps(DOWN-STREAM)
Actual IP throughput achieved during the test was - 3711 kbps

That throughput for the quoted profile is quite reasonable, I think. The profile suggests that your router has dropped the connection and re-synched at lower speeds. For it to rise, you need a minimum of three days of higher-speed syncs. One low one and you start again.

I'm not sure what the tester meant about your router, never having seen the error message myself. Did it come with a setup CD?

Not that i can remember, there's not much in the way of Identification on the router itself.
Iam nearly sure its a conexant one, all it says is; 4 Ports ADSL Router , P/N 81180026 on the bottom and a serial number.
the router itself must be about 2 to 3 years old by now.

I wonder if it itself is limited as to what it can through-put?

It might be limited by what it can sync at but not what it will throughput. You might want to try a more modern router if you want to get the maximum sync rate for your line.

Your IP profile of 4000 suggests that you have had a sync in the last 3 days of around 4500 kb/s. Leave it until the weekend and do another test. If the system is working properly, and based on your sync rate of circa 6000 kb/s then it should increase to around 5500 kb/s and your download speeds should increase.

Just for clarification, the minimum sync speed for a 4000kbps IP (BRAS) profile is 4544kbps, and for a 5500kbps IP profile, the minimum sync is 6240kbps.
The router needs to hold sync, above the minimum, for three days before the IP profile will increase.

Another succesfull BT speedtest;

IP profile for your line is - 4000 kbps
DSL connection rate: 448 kbps(UP-STREAM) 7072 kbps(DOWN-STREAM)
Actual IP throughput achieved during the test was - 2997 kbps

As far as I can see, the possible connection of 7072Kbps has went up and the actual of 2997Kbps has went down, Will give it a few days and see what happens.

I was thinking about a more moder router today, could be money well spent

So Ade, would you agree with Last Man, that perhaps a more modern router would help the sync rate?

To be frank, your results are not at all bad. You have an IP profile of 4000 which is the maximum possible theoretical speed test that the BT exchange equipment will allow on your line. If you get more than 3000 for a speed test on a line with an IP profile of 4000, I would say that your connection is working well.

I am basing my suggestion that you may benefit from a new router on the fact that you have a 15db SN margin downstream. It should be nearer to 6db.

When you resynchronise your router the Exchange equipment will set the fastest rate it can to achieve a 6db SN margin.

If your router is showing 15db of SN margin this can either mean either of the following:

1. Your SN margin varies a lot between night (typically a low SN figure) and day and your router last did a resync in the night and you are looking at the stats during the day.

2. The BT equipment has set an unusually high SN margin for your line. BT will sometimes do this if the line conditions are particularly poor.

3. Your router is not fully compatible with a rate adaptive service such as ADSL Max.

Before you buy a new router you could try eliminating the possibility that it is 1 above by rebooting your router during the day. If it synchronises to the maximum speed of 8128 kb/s then it is likely you have a noisy line at night. If it still synchronises at around 7000 kb/s with a SN margin of higher than, say, 10db then it could be either 2 or 3 above.

Unfortunately I know of no way of telling for definite whether BT have set a higher than normal SN margin target for your line, so if you buy a new router it could still be no better than your old one.