Kitz Forum

Broadband Related => ADSL Issues => Topic started by: gary on September 13, 2006, 02:09:43 AM

Title: line sync and probale speed
Post by: gary on September 13, 2006, 02:09:43 AM
Hi,im nearly done with my 10 day testing period of adsl max,my stats as of now are:

atten:63

snr:5

sync:2144

(downstream)

my snr was higher than that before max but i expect it gone down due to the speed increase.My question is,my sync is 2144 and my downstream seems to have settled at 117kB/s which is near as dammit 1mb,i dont know much about syncs and overheads,but when my profile is set shouldent i be attaining 1.5mb or possibly even 2mb?

Thx for any assistance.
Title: Re: line sync and probale speed
Post by: roseway on September 13, 2006, 07:42:01 AM
Well yes, you should be able to get a bit more, but Max is full of ifs and buts and nothing is certain. You may have a stuck BRAS profile limiting you to 1MBps, or there may be congestion at your exchange or something of that nature. I see that you posted your message in the small hours, when congestion shouldn't really be a problem, so your BRAS profile looks like the suspect.

I suggest that you give it a few more days, and then if nothing improves take it up with your ISP.

Eric
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 11:07:06 AM
Your profile will be based on your lowest sync speed over several days.
Therefore, although you may be syncing at 2144 presently its possible that during the past 3 days you have synced at a lower speed that has affected your bRAS profile.

Out of curiousity what speed product was you on prior to max?
Title: Re: line sync and probale speed
Post by: gary on September 13, 2006, 11:29:39 AM
hi

thanks both for your replies.

As i mentioned earlier im on day 9 of my training period,so half expect to be up and down.I am lucky enough however to be infront of my pc for most of the day/night,as i work from home,and am very fanatical about my internet connection so have been monitoring it closely.

My sync has been above 2114 since near enough day 1 since it changed from 576(previously i was on 512kB fixed line,the fastest isp would let me,with a 3.76 km from exchange,as crow flies)

The only problem i have encountered over the last few days is my download speed dropping from the steady 117kB i have been getting to periods where it is only 30kB,but my line stats havent altered at all when this happens.Again im putting this down to the training period,and am just hoping my profile gets set to 1.5 to 2mb tomorrow when it ends.

2 other things i forgot to mention,my upload speed has always been steady at 45kB with a sync of 448,and ive read about the stuck bras profile scenario,but is it only fast lines with high syncs that are usually prone to stuck profiles?
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 12:14:39 PM
Yeah the stuck bRAS for some reason did seem to affect those that were on the better lines  - These were previous 2Mb lines that were stuck with a 2Mb bRAS profile. I believe BTw has supposedly fixed the major causes of this.

However there is the odd one or two that still creeps through.. 
One of those that I saw within the past couple of weeks was actually stuck at 512kb - which happened to be the service he was on previously.
Therefore it follows that if you had a stuck bRAS then you would also be stuck at 512kb speeds.
When you get a stuck bRAS.. your connection just continually *flatlines* at that particular speed.

Since you have been getting 117kB/s (936 kbps) which seems spot on for 1Mb.. then I dont think you have this problem.

As mentioned your bRAS profile will be taken from the lowest sync speed over the past few days.

Theres a table at the bottom of the page which shows what throughput speed you will likely get based on your minimim sync speed.
http://www.kitz.co.uk/adsl/maxdsl2.htm

So you can see from that if 2114 was your minimum sync speed then you would expect your throughput speed to be 1.5Mb.


If there is periods when you only get 30KB (240kbps) and this only happens during peak times, then there could be other reasons why you see these lower speeds such as contention.

If it was your bRAS limiting you to 256, then I would expect you to be limited to this 24/7 for a few days, as it will take 3 days of consistantly higher sync speeds to raise your profile back up again.

Your ISP should be able to tell you your bRAS profile.

One of the unfortunate things about maxdsl is, that BTw can drop your profile within about 75mins if you get a lower sync speed, yet it takes up to 4 days before it is raised.  :(
Title: Re: line sync and probale speed
Post by: gary on September 13, 2006, 12:52:21 PM
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fimg135.imageshack.us%2Fimg135%2F2876%2Fscreenhunter001nz7.jpg&hash=90793717ebb2cd9741062c3f73f7ddd0)
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fimg80.imageshack.us%2Fimg80%2F1791%2Fscreenhunter002go6.jpg&hash=95f28dbaf9ace1ca5838efb7835be797)

Ok heres my speed tests i been carrying out through the 10 day period,told you i was fanatical about my connection  :lol:

Throughout all these testsmy sync has remained over the 2110 mark and snr about 5,i hope this will give you some guide to whats going on,as i havent a clue?

and my router stats at this present time:

(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fimg135.imageshack.us%2Fimg135%2F1534%2Fscreenhunter003tv4.jpg&hash=a33e27257c4bde7840216743f1e92cc7)

**1.30pm update** -back up to 117kB download speed now,so it looks completely random and contention can be ruled out maybe?
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 01:39:58 PM
hmm  due to the fact that for various times within the same day you have got speeds that are pretty poor
(31.1 kB/sec 12.01pm 12-9-06) (13.4KB 1.33pm) to good 1Mb speeds (118.1 kB/sec 5.56pm 12-9-06) and the fact that they vary throughout the day.. and that it happens on several days........
I would say that isnt down to a bRAS profile or not even max related.

If those sort of swings were happening every day as a result of something that the DLM was doing, then by now your IP profile would have kicked in and you would be limited round the clock.


Who is your ISP?
I would ask them if they can tell you your bRAS profile (IP data rate) jus to completely discount that theory and for your own curiosity....
but tbh looking at it from here, that looks like its something else that is causing those swings.... possibly even contention.......
But even that doesnt make sense because some of your better speeds are at peak time when you would expect contention to hit the hardest. Some of your worst speeds seem to be main part of the day.   ???  ???

Ive got to go out now... but if any of the other guys on here can see a pattern in those speeds or any other suggestions then please speak up.
Title: Re: line sync and probale speed
Post by: gary on September 13, 2006, 02:01:35 PM
Thx kitz,you been a good help so far in trying to determine the prob.

My isp is v21,and ill raise a ticket with them tomorrow after my 10 days is up,as its an easy get out clause to blame it on that and close it.

My router is a trendnet tew 435-brm..theres not much info about this on the net,apart from a lot of french sites,but i think it to be an ok kind of router with it keeping me online 24/7 for long long periods of time.

I have one bt socket in my home(master),which is an inline filter jobby,that also is about the best solution i can get i think?,with no extensions from router to box,only 1x5m rj11

theres a little more info for you guys here to digest,and ill fill you in with the probaly farsical excuse v21 give me tomorrow.

Once again thx all for helping,and ill keep you informed of what happens.
Title: Re: line sync and probale speed
Post by: roseway on September 13, 2006, 03:18:33 PM
You can now find out your own BRAS profile speed by going to http://test.speedtester.bt.com:50301/ and entering your telephone number. You can only do this when connected via that telephone number. After a pause it asks you for your ADSL username, then it runs the test and gives you a report like this:

---------------------------------------------------------
Test1 comprises of Best Effort Test:
    IP profile for your line is - 4000 kbps
    DSL connection rate: 448 kbps(UP-STREAM)  4544 kbps(DOWN-STREAM)
    Actual IP throughput achieved during the test was - 3659 kbps

If you wish to discuss these results please contact your ISP.
---------------------------------------------------------------

As you can see, my profile is set at 4000 kbps.

You may have to make several attempts to get it to work, as it often gives up in the middle after a longish delay and says that the system is busy.

Eric
Title: Re: line sync and probale speed
Post by: gary on September 13, 2006, 03:46:53 PM
-------------------------------------------------------------------------------------------------------------------------------------------------------
Results Image not loaded

Test1 comprises of Best Effort Test:
    IP profile for your line is - 1000 kbps
    DSL connection rate: 448 kbps(UP-STREAM)  1152 kbps(DOWN-STREAM)
    Actual IP throughput achieved during the test was - 922 kbps

If you wish to discuss these results please contact your ISP.

If you are experiencing problems with specific applications, servers or websites please contact your ISP for assistance.

Your test has completed please close this window to exit the performance tester.
------------------------------------------------------------------------------------------------------------------------------------------------------

thanks for that link,at least i can see im set at 1mb now?...but the question being wheres the missing 1000 from my router ds sync?,or is this normal?
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 05:16:04 PM
You can now find out your own BRAS profile speed by going to http://test.speedtester.bt.com:50301/ and entering your telephone number. You can only do this when connected via that telephone number. After a pause it asks you for your ADSL username, You may have to make several attempts to get it to work, as it often gives up in the middle after a longish delay and says that the system is busy.

lol..  Im glad it was you that posted that... as its meant to be "under wraps"  :D
afaik its still in beta, (- although they have amended a few things since the first version).
However it cant cope with a lot of traffic - hence why you sometimes have problems running it.
Someone's obviously leaked the info..  since I saw mention of it on another forum a couple of days ago too.
The other thing is its no good for diagnosing such things as contention, since you still pass through your ISP pipes.

But at least its a damn site more accurate than a certain LLU speedtest a few of us were testing.
Now that gave me hellishly good speeds. - 16-32 Mbps connection anyone? :lol:

Title: Re: line sync and probale speed
Post by: roseway on September 13, 2006, 05:24:37 PM
I don't fully understand these figures, but I think that the "DSL connection rate" is the connection rate as given in your profile, the difference between the 1000 and 1152 being overheads. Your actual router sync rate is in effect being throttled to 1152 in the DSLAM.

After a few days of continuous sync at a higher rate your profile should reset to a higher value. If it doesn't then you'll need to ask your ISP to get it unstuck for you.

Kitz understands these things better than I do and may well tell me that I'm talking through my hat. :)

Eric
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 05:28:09 PM
Quote
at least i can see im set at 1mb now?...but the question being wheres the missing 1000 from my router ds sync?,


A sync speed of 2144 is going to give you a bRAS IP profile of 1500.
To have a profile of 1000, all I can assume is that at some point you must have synced between 1152 and 1728 kbps.
This is one of the annoying things about IPStream dslMAX, in that even though you are now syncing at the higher speeds then you will still be rate limited to 1Mb speeds because of what must have been a lower sync speed at some point in the past few days.

Explanation of how dslMAX works. (http://www.kitz.co.uk/adsl/maxdsl2.htm)

As mentioned in one of my posts above you would have to continously sync at speeds over 1728 kbps for at least 3 days before you get a 1.5Mb profile. 
If you can get your sync speed over 2272 kbps and keep it there - then you will get a 2Mb profile.

Theres a couple of things you can try to get your SNR increased, and therefore more chance of syncing at a higher speed on my LowSNR page (http://www.kitz.co.uk/adsl/lowSNR.htm).
Although that was written pre-max - the same theories still apply.
Title: Re: line sync and probale speed
Post by: gary on September 13, 2006, 05:39:13 PM
Ok,thanks very much for this..i think this has cleared things up now.

I have put a ticket into my isp and will await a reply,and post the outcome here.

Once again thankyou for enlightening me a little,and i now have plenty to fire at my isp when the BS starts flowing tomorrow  :'(
Title: Re: line sync and probale speed
Post by: kitz on September 13, 2006, 05:44:14 PM
Youre quite correct roseway.

Yes the IP profile is the maximum speed that your line is likely to achieve.
One of the things that I said was it was quite confusing,
Even though my data rate as set by my ISP is 8000...  the results of "One I did earlier" was

Quote
Your configured download throughput speed for this service is 7150 k

Test1 comprises of Best Effort Test:
    IP profile for your line is - 7150 kbps
    Actual IP throughput achieved during the test was - 4407 kbps

So you can see it rates my IP profile as 7150kbps.. which is the max speed I am ever going to see after ATM overheads if things were running full pelt on the VP and ISP level.

TBH though roseway Im still not sure quite how accurate the recorded speeds are... ( I may do some further testing when I get chance to see if it has improved)... **
But during the original testing even though I got the above results from that test..  speedtests on other speedtesters such as AG and BBMax taken at the same time - none of them gave me below 5.5Mb.
Some of the other feedback I gave was "why is it returning lower results than the *real world* speedtests?"


** Its too busy right now and I cant connect
Title: Re: line sync and probale speed
Post by: gary on September 14, 2006, 10:09:24 AM
Quote
13/09/2006
14:56:44    Customer    CONT: Router setup information provided

Hi

My 10 day traing period ends today for max adsl,however i seem to be encountering problems with speeds issues.

Since the upgrade my router has synched at a steady 2100-2200 figure(i have been checking constantly),but my max download speed seems to be at 117kB,which as you know is near enough 1mb,this is my first problem.

1.I should be set on a profile by now of either 1.5mb or 2mb with that steady sync?,and it looks to be set at 1mb.

2.through various times of the day my speed goes down to 20-30kB frequently from the stable 117 i have been attaining,this is also an issue that needs fixing pls?

Also could you tell me what my profile is set at,as this should be the one thats cast in stone now when my testing period ends today sometime,and if it is 1mb,why?

Thx,ill keep this ticket open as it may be an ongoing thing until things can be altered.

---------------------------------------------------------

Quote
14/09/2006
09:31:44    Technical Support    Hi Gary,

Your account profile has no bearing on the speeds you can obtain - ie, if we had your profile set to 512K but the line was provisioned at 2MB, you would still get 2MB speeds - the profile here reflects your billing.

After the line training has settled, the speeds you get should be at least in excess of 1MB - can you provide the speed results you see from the site speedtester.bt.com - making note of the required change to your ADSL login prior to running the test?

Kind Regards,
Paul
Technical Support

-----------------------------------------------------

Could be the start of a long day?  :(

Title: Re: line sync and probale speed
Post by: roseway on September 14, 2006, 10:20:34 AM
There seems to be a little confusion here, Gary. The BRAS profile which we've been talking about is set automatically by the BT equipment, not by the ISP. Sometimes it can get stuck, in which case BT can unstick it manually; to get this done you have to go through your ISP, who can ask BT to do it.

The reply from Technical Support clearly has a misunderstanding in thinking that you were talking about their account profile for you (something quite different). It might still be worth going through the rather tedious process of using the BT speedtester, but really I think you need to wait a few more days for the training period to settle.

Eric
Title: Re: line sync and probale speed
Post by: mr_chris on September 14, 2006, 10:29:23 AM
Hmm...

It may well be that the profiling at the ISPs end is nothing to do with speeds. Some ISPs do this, some don't.

An ISP has no direct control over the BT BRAS profile setting (which does affect your speed) so they can't change it.

The new BT speedtester now reports sync speed as you know - or should I say, the sync speed as recorded by BT, rounded down to the next 'step'. For example, I synced at 7100 twice, and suddenly the sync speed recorded was 6816kbps, and my IP profile was set at 6000.

Any low speeds could be (a) the result of contention on the line or (b) the result of line errors on your line. I've looked back and see a large number of errors in your screenshot. Your router is obviously based on the same Texas Instruments AR7 chipset that the Netgear DG834v2 is based on. Good at maintaining sync at low SNR values.. the errors will ramp up though and you will get poor speeds - but at least you don't lose sync. This happens to me - presumably it's happening to you too, judging by that amount of errors!

Hope this helps? :)
Title: Re: line sync and probale speed
Post by: gary on September 22, 2006, 12:21:41 AM
Hello again all

Just a final update to my adslmax tribulations to all those that are interested.

First of all a big thankyou to all that have contributed in this thread,your help as been invaluable,and in all honesty i would still probaly be sat here with crap speeds now if it wasent for you guys,and a few other on diff forums.

The end result is i now have a bras of 1500 and a download speed of 176kB/s with a stable connection.I had a slight prob with it being stuck on a 1000 after testing period,but seems to be upgraded today after chasing up isp.

All in all i am happy with that speed considering my poor line to exchange(63 atten,snr 3-5),and it a lot quicker that the 60kB/s most isps were saying thats all i could get.

I couldent finish this post without slipping 1 more question in  ;),im greedy and want to eek my profile up to 2000,my router is synching around the 2100 mark,and steady....i may be wrong but i read somewhere the threshold for a 2000 bras is around the 2200 mark?,is there any possibility at all of me raising my router sync,just that little more to see if i can get the 2000?

I also read here that resyncing at certain times of the day will give you a better chance of a higher sync,what are the best times pls,and what sort of increase/decrease will be applicable if hitting the best and worst times of day?

thankyou again all
Title: Re: line sync and probale speed
Post by: mr_chris on September 22, 2006, 01:31:28 AM
2272 is the old fixed rate for 2Mb, so it's kinda nearer 2300. Basically the best time of the day to sync is when your SNR is reporting at its highest value, and only then if it's above 6dB, otherwise you will probably see a drop in speed. There's no pattern to it, although a lot of people find their SNR decreases at night due to more interference being around.

Then of course you've gotta hope that the SNR doesn't go down enough to force your router to resync.

You'd have to maintain a steady sync of > 2272 for at least 3 days in order to qualify for a 2Mb BRAS profile - no mean feat with your line stats!

A word to the wise - don't be tempted to keep rebooting too many times in a day or else your line may be throttled to a really low rate (I've seen reports of some going down to 160kbps!) and would be stuck there for 3 days - not nice!