Line Speed Training

[GrimDad]

I would like to know if your are already on an up to 8 meg connection and you move to another isp will the line under go speed re training?

[Rik]

Unless you move from LLU to IPStream, there would not normally be a re-training period. I moved to IDNet last year and just brought my profile, MSR/FTR etc with me, which seems to be the general experience.

[GrimDad]

Thanks Rik & Hi from my other post.

Reason i asked is:

I joined an isp in May after the ten days my router was syncing at 3100-3200 down and my ip profile was 2500.  I enjoyed 3 months at these speeds then my ip profile started dropping first to 2000 then 1250 and now 1000.  I contacted support who arranged for a BT engineer to visit. He check my line at the exchange then came to my house.  At my house he re-crimped connections to my house removed my faceplate connected his laptop and tested the line. He then fitted a new faceplate with builtin filter and retested.  He then told me my line length is 3809 metres to the exchange and said my line should support a 3meg connection no problem.  He then made a call to have my profile reset but couldn't get through so he said if my profile didnt go up in 36 hours to contact my isp and get them to contact BT.  I have done this and now my isp is telling me that my ip profile is correct at 1000 and 899kbps throughput and I shouldn't take any notice of what the BT engineer said.

Now who is feeding me the BS here my isp or the BT engineer?

[Rik]

You sound like you have the same sort of degradation on your line as me, though way more severe.

What are your line stats - attenuation, noise margin and sync speed? Armed with that, I'll take a guess at whether I would trust your ISP or the BT engineer.

[Lance]

My gut instinct would be to trust the BT guy.

Welcome to the forum GrimDad

[Rik]

My gut is with you, Lance, but the figures will say for sure.

[GrimDad]

ADSL Link Downstream Upstream
Connection Speed 2304 kbps 832 kbps
Line Attenuation 60.0 db 31.5 db
Noise Margin 3.8 db 6.0 db

Router sync is up and down like a yoyo in about an hour it will sync 1250 then go back up to 2200-2300.

Just did a bt speed test
Test1 comprises of Best Effort Test:  -provides background information.
   IP profile for your line is - 1000 kbps
   DSL connection rate: 832 kbps(UP-STREAM)  2304 kbps(DOWN-STREAM)
   Actual IP throughput achieved during the test was - 903 kbps

[Rik]

I think your ISP may have been telling you the truth.

Your profile for that sync speed should be 2000, so that suggests to me that the line is very unstable and has been flapping. In that situation, the profile is going to struggle to recover. You do have a long line, on fixed rate you'd only get 1Mbps for example, but it should be able to go faster than it does, but not, imo, at 3Mbps. If the engineer was correct in his distance to the exchange, I suspect that you have aluminium on your line (as I do), which increases the attenuation compared to copper.

Have you checked your internal wiring, to ensure that any problems are not local (do you have an NTE5 master socket, the type where the bottom part of the faceplate can be removed? If so, have you tested from there to see if the figures change?). If you can improve the stability of the line, you can probably get to a profile of 2500.

I note that you are paying for a premium package. With your line, it's probably a waste of money (unless you need the higher u/s speed), so you may want to regrade.

[GrimDad]

I have tested using the test socket and used 3 different routers, filters and different cables and results are always the same.

I'm on the premium for the upload speed...I host a server for online racing (rFactor) and also have a few websites.

I'm just struggling to understand why i can have a 2500kbps ip profile for 3 months solid then it just decides to go to 1000.

I've had fixed rate 2mb before and never had problems with that..

Thanks for your help and opinions though...

[Rik]

The profile is a direct relationship with the sync speed, so if you had a higher profile for three months, you must have had a higher, and stable, sync between 2848-3423. Given your existing sync and profile, you must have dropped to a sync speed of between 1152-1727 in the past five days or so. Your target noise margin hasn't been increased, though, which is good news (when that happens, the BT software considers your line very unstable). I'd suggest that something on your line, possibly as simple as a joint, has gone 'out of spec'.

If you've eliminated your internal wiring, I'd suggest contacting your ISP again and ask them to get another engineer out. If you have your line stats from when you had the higher profile, it should help your case, but it depends, to an extent, on what value is recorded as FTR for your line.

If you've had a 2Mbps, fixed-speed, connection, it suggests that your line once had a 48db attenuation (or better). BT won't supply more than 1Mbps between 49db-62db. In that situation, it should be possible to get a significant improvement in your connection.

With this sort of problem, you find out how good your ISP's support is - a good ISP will pursue BT until they have exhausted all possibilities. Good luck.

[GrimDad]

Thanks Rik....your comments have been taken onboard and i have already requested my isp push BT for another engineer to do a more thorough test on my line.

I do have line test results from the bt tester and router stats too so now its time to wait and see what if anything happens.

Thanks again for your time and views on this matter.

[Rik]

Let us know how you get on, or if we can help at all.