[Chrysalis]

With NTL I suffered some heavy contention and proxy problems but at twilight hours I was able to achieve their advertised max burst speed. They also sent out engineers to me on fault reports.

This post is to give a BT comparison.

I live 1.65km from the exchange (stright line) and generally people are told to expect usually between around 125% and 250% line distance, it can be above and below that tho. So if 250% would have been around 4.1km.

My line is around 3.8km at a guess based on its performance and attenuation.

I signed up to nildram adsl max service 1 day after my line was installed and the service was advertised as upto 8meg broadband. The checker said I should expect speeds of 4.5mbit upwards.

First point I should make because the way BT have implemented adsl max noone can ever get 8mbit the max they can reach is 7.15mbit because they no longer add overheads on top of the synch speed it now includes the overheads. So about 10% is lost.

Secondly BT operate a seperate cap to get around ATM issues, BRAS automatically controls this cap based on the synch speed, it is in 512kbit steps so if you synch just above a previous step its fairly optimal but if just below a step then some of your synch bandwidth is wasted. Obviously at lower speeds the amount wasted is a higher % of total. Also if the synch drops BRAS will react within 75 minutes, but when the synch speed rises it takes BRAS upto 3 days to react, meaning their is an artifical cap throttling you for 3 days after, in some cases including my case if you get a low synch at least once every 3 days no matter how short it is the higher synchs will be capped/throttled down to the lower synch speed. In my case I would be synched at 6000kbit and be capped at 3mbit.

So I get activated and synch at around 6200kbit, fairly excited the net is snappy and I am seeing speeds upto around 600kB. No problems for a few hours. Suddenly the modem loses synch and I have no connection for a few seconds, after that back to the snappy internet. Suddenly about 10 minutes later it happens again , this repeats throughout the day and night, after the first night my router had disconnected 109 times.

Now I think BRAS wasnt fully enabled for the first day or so on my connection because everytime the synch speed changed up or down my speeds reacted instantly, but eventually BRAS was turned on and I became victim to its evilness.

The situation was very bad until I managed to get them to turn interleaving on, interleaving is something that corrects errors at the expense of latency and it usually saves a lot of desynchs. Obviously this wouldnt please gamers. After this was turned on pretty much all of my nighttime desynchs stopped, at night I get the usual AM interference that most people can expect and the weakened frequencies just generate FEC errors but not much other harm done. At nightime my line is probably normal behaviour and their product worked as it should.

However during the daytime it became evident to me thanks to me using some clever software to graph my SNR (signal quality) that their was some non standard behaviour occuring on my line, at this stage it also became apperent that BT will do anything to avoid sending out an engineer, it was also apperent that they have low standards of quality regarding their phonelines. The interference is (a) sudden, (b) large, (c) not on am frequncies and in fact on the lower downstream frequencies close to the upstream frequency, (d) only occuring weekdays not at night or weekends. Dispite this BT insisting its extension cabling, streetlights, local appliances, normal am radio intereference. I have only a master BT socket, I spent money to rule out router/cabling/filter faults, and the fault was in the day and not at night, am interference is stronger at night and on a completely different range. These drops in signal were just about half of the entire signal itself, so dispite them raising my snr margin which is supposed to be a cushion to take the fluctuations it had no affect. The affect was the router lost synch, then their was less snr during the resynch so when it resynched at the target snr it was synched around 2000-3000kbit lower then normal and you guessed it my BRAS capped me accordingly. I could synch higher again usually within minutes and stay synched high all night and all weekend, but the high sync means nothing because BT have a nice BRAS cap throttling me down to a speed I synched at just for a few minutes during the day.

So eventually a engineer comes out, I get a unfreindly call from BTWholesale telling me this isnt procedure and I am very lucky blah blah, the engineer is booked. He turns up admits fault isnt my end but hasnt a clue what the fault is, he switches me to a shorter copper pair basically meaning shorter route to exchange but the gain was very small approximately 1/50th shorter, I asked where the cabinet was and when he told me it seems its further away from the exchange I am, so my line already is going to that and then doing a u turn back to me, for all I know its doing that about 3 or 4 times on the way here.

He went back and within 20 minutes I get an automated call from BT saying fault closed. But of course the problem is still there, except now it does just about stay synched when the snr drops down meaning if I am lucky my BRAS will raise to 4mbit after 3 days, but remember one desynch and resynch at low speed the cap goes back down.

My point in brief is, BT and its resellers are getting away with selling a upto 8mbit product, that cant provide 8mbit to even 1 customer. Their old fixed speed products were synched at 2.2mbit and 1.1mbit for example as they covered the overheads. No mention of a changed algorithm for calculating speeds anywhere to the customer so straight away customer is mislead. Next if the phoneline isnt short enough or just poor quality or if you really unlucky long and poor quality then you will never ever reach 8mbit.

I am still trying to get my head round how a product can be sold as upto 8mbit to a customer who will never ever reach 8mbit, the ofcom regulation is very weak regarding this for instance.

1 - Any customer getting below 8mbit is effectively subsidising the customers getting superior service since they pay the same price, someone getting say 2mbit on adsl max couldnt simply downgrade to a 2mbit product since they wouldnt qualify for fixed 2meg adsl as the limits are much more conservative.

2 - The always on factor apperently doesnt apply to BT they class lines that occasionally desynch as normal behaviour, seems it doesnt bother ofcom either.

3 - The first 10 days of the service BT reject all fault reports, the line trains itself and sets a fault threshold during this period, after the 10 days if the line synchs lower then the fault threshold BT accept a fault, the serious flaw in this is if a fault threshold is set on a already faulty line it will be artifically too low.

4 - customers have to contact isp who then contact BT, if the isp doesnt play game then a fault may not even get escalated to BT at all leaving a very frustrated customer.

In the past I have moaned about ntl but at least with ntl their was an option to downgrade if you felt the higher speeds werent reached enough and their highest speeds are generally in reach to just about all their customers.

I wonder what any thoughts are on this, personally I think ofcom should tell BT that any line that synchs below 8mbit should be price deducted accordingly so revenue is reduced, this would defenitly kickstart them since profts are then affected, the ASA should also step in and make them call it 7mbit rather then 8mbit and of course redefine it.

To add my phone line is much worse quality then the ntl line in the property, the BT one sounds like the volume is turned down and performs slower on dialup, however BT count it as faultless. Ben CEO of BT didnt even reply to email sent to him. So I guess he isnt that concerned about customers after all.