I now have 8MB Broadband... sort of.

marksi · Fri 23 Jun, 2006 18.52

I have BT Broadband... and have today been upgraded from 2MB to 8MB.

Modem/router connected at 8128kbps downstream and 448kbps upstream. Fab.

But when I do any online speed test is shows the actual connection speed as being consistently around 1900kbps.

Anyone know why that would be?

Gavin Scott · Fri 23 Jun, 2006 18.57

marksi wrote:I have BT Broadband... and have today been upgraded from 2MB to 8MB.

Modem/router connected at 8128kbps downstream and 448kbps upstream. Fab.

But when I do any online speed test is shows the actual connection speed as being consistently around 1900kbps.

Anyone know why that would be?

Your contention ratio (how many people sharing the *actual* 8MB) is probably quite high. It is dependant on how many bandwidth hungry people are connected.

From google definitions: With most broadband technologies, some of the bandwidth is shared between other users. For example, if the service is contended or oversubscribed at 20:1, it means that you share the bandwidth with up to 19 other users. Basic ADSL services in the UK (mainly using the BT network) typically have a contention ratio of 50:1 with the more expensive or business packages having 20:1.

marksi · Fri 23 Jun, 2006 19.01

Am understanding that but on 2MB the speed was almost the same.

Not as bad as friend's "8MB" from TalkTalk that I set up for them last week which gives them a consistent 300kbps.

I guess you get what you pay for...

Gavin Scott · Fri 23 Jun, 2006 19.24

marksi wrote:Am understanding that but on 2MB the speed was almost the same.

Then you were very lucky! I wonder if you happened to have that line to yourself (although *how* is anyone's guess).

Sput · Fri 23 Jun, 2006 19.25

It might be that BT MAX bug people have been complaining about - the sync speed and throughput speed are updated independently of each other and this bug is stopping the throughput being changed to something similarly fab. Lots on this on ADSLguide.org.uk and ispreview.co.uk

marksi · Fri 23 Jun, 2006 19.35

Sput wrote:It might be that BT MAX bug people have been complaining about - the sync speed and throughput speed are updated independently of each other and this bug is stopping the throughput being changed to something similarly fab. Lots on this on ADSLguide.org.uk and ispreview.co.uk

Hmmm.. this may be the problem!

Initial BRAS data rate profiles when switching to Max are those of the previous service, for example 2M. They should change to match the modem after ~75 minutes however it is fairly common for this not to happen, especially if you get the full 8128 sync speed. Switching the modem/ router off for 30 minutes each day may wake the system up but if it doesn't change in 10 days talk to your ISP.

If the BRAS rate is stuck at 2M you will see speed tests of 1800-1900 kbits/s even with the modem sync speed at 6 or 8M.

shaun · Fri 23 Jun, 2006 21.32

One fix that has been touted around is to deliberately make the router or modem sync at a lower speed. This can help reset the BRAS profile.

Try plugging an unfiltered phone in, taking it off hook and switching the router off / on. This may cause enough interference to make the router sync at a speed other than 8128 (the upload won't normally move) and reset the bras profile.

Obviously if you succeed, unplug the phone and reboot the router and you should sync at 8128 again.

Andrew Wood · Sat 24 Jun, 2006 09.48

Also, don't forget that at different times of day you'll getter varying throughput speeds - even through your connection will be static at 8192 - for the contention reasons mentioned above.

Initially, once I'd managed to get PlusNet's stable rate up to 8000 to match sync speed (by switching the router off for half an hour one day), in the evenings I'd get no better service than the 2mpbs I'd previously had. Only first thing in the morning (4am to 7am) would I approach anything like MaxDSL speeds.

Zen Internet is clear about this on its website:

- Actual download speeds will be no higher than 7150kbps.
- Average download speeds recorded to date by BT average between 5-6Mb.
- Fluctuation in line speed is expected to occur within the first 10 days before the line speed adapts.
- It is likely that speeds no greater than 2Mb will be achieved at peak usage times.

Also, I'm not sure whether this is the case or not, but I believe that some exchanges are not geared up for the extra amount of data requested to come through them causing backlogs. It felt that way with my exchange, though data throughput in the evenings has improved significantly in the past couple of months.

marksi · Tue 25 Jul, 2006 13.26

BT are now arguing among themselves as to the problem.

BT Broadband accept the throughput is less than half what it should be, but when they report it as a fault to BT Wholesale, they say it is "within acceptable limits".

My line has settled on a constant 6848kbps downstream, but the throughput is consistently 2MB, even in the middle of the night.

nidave · Tue 25 Jul, 2006 21.43

what ever you do dont reset the moden constantly - you will cause your profile to set at a lover speed as it thinks there is a problem with the line.

Moveing from cable and am having nightmares about the whole ADSL thing.

Nick Harvey · Tue 25 Jul, 2006 22.41

nodnirG kraM wrote:Q: What do you do if your lover starts smoking?

A: Find a product to reduce the friction!