In reply to a post by Lethe:

What I find frustrating is the 'usual' replies to the OP when something happens like this.

Like me, NOTHING changed except the sync speed connection.

If "NOTHING" changed the sync speed would be the same. So something changed somewhere, the challenge is to find what.

I have downloaded a couple of stat programs - RouterStats and RouterStats Lite.

The lite version works, but only gives SNR and connection, i cant get the full version to run. Ill hunt around and see if i can get it working.

Where i have said "switch" perhaps distribution point would be a better description.

Each room has Socket on the wall which is the BT socket. These in turn feed to a central location (distribution point) in the building and then i assume goto the exchange.

I have monitored my router stats for the past 18 hours and it remains solid on 6.1db SNR and Line Attenuation is steady at 23.5db. This is pretty much what it has been on since its installation. The SNR sometimes fluctuates down to 5db, but i have never seen it disconnect when it does this - and its not that often it moves from 6.1db

the implication is that something has added interference in the 300 kHz - 1 MHz band and that is reducing your available sync speed.

If you're on a military base there might be a few possibilities for comms or radar equipment to do that.

If the wiring is dodgy then another room getting ADSL could impact on you, or someone could have a dodgy power supply or appliance radiating interference nearby.

An AM radio tuned off-station can be used to listen in to the frequency bands for obvious strong interference. Getting your neighbours to run everything off for an hour might help narrow it down.

If you have Router Stats Lite working that will be enough.

Get it to record and plot SNR and Sync speed every 30 seconds for at least 24 hours. SNR will vary by the seconds and during a day you will see an slow rise and fall of maybe up to 3 dB that is normal.

Then, go and talk to your neighbours, and ask them to turn off everything that they have in their room. Log the times for each room and then go and look at the graph were there any re-syncs? or large SNR changes?

There is the possibility that something outside the building is causing the problem too - are there any construction works on your base?

When I say 'nothing' I mean at my end - obviously something changed, but the BT engineer after all the tests said nothing is wrong.

I agree with the OP that as the 'accepted' government stance is that everybody should get at least a 2mb connection, this is now taken as the acceptable bottom line no matter what is wrong with your adsl connection - if you get =>2mb, all is 'OK'.

Nick

An AM radio tuned off-station can be used to listen in to the frequency bands for obvious strong interference.

Further to Phill's comments, if you can find a portable MW radio tune to 612, and listen at this frequency. If being drowned out by noise, it would be well worth hunting around for the noises strongest point. Bear in mind that some electrical equipment can give noise which isn't a source of interference.

The most commonplace noise/interferer would be a Sky box, this is usually quite a deep 'growl' on the radio. Since it is usually connected into a telephone line, it has an easy path to get on to the network.

Does your router provide errors counters, CRC's FEC's and HEC's, if this IS interference, then these counters may show very high numbers of errors. Again, if it IS interference, I suspect you are some way from the source, because if closer, you'd be seeing drops in sync, maybe even no sync at all.

In reply to a post by Lethe:

I agree with the OP that as the 'accepted' government stance is that everybody should get at least a 2mb connection, this is now taken as the acceptable bottom line no matter what is wrong with your adsl connection - if you get =>2mb, all is 'OK'.

BT lines have fault reporting thresholds for ADSL and VDSL services, these are based on early connection rates. Numpties in call centres may not understand, but sync below FTR is a reportable fault.

In reply to a post by yarwell:

In reply to a post by Lethe:

I agree with the OP that as the 'accepted' government stance is that everybody should get at least a 2mb connection, this is now taken as the acceptable bottom line no matter what is wrong with your adsl connection - if you get =>2mb, all is 'OK'.

BT lines have fault reporting thresholds for ADSL and VDSL services, these are based on early connection rates. Numpties in call centres may not understand, but sync below FTR is a reportable fault.

But if you go the the BT speedtest site and do the diagnostics thing:

http://speedtest.btwholesale.com/

this is what I get (remember, I am less than a mile from exchange in a big city):

Download speedachieved during the test was - 2.76 Mbps
 For your connection, the acceptable range of speeds is 1.2 Mbps-4 Mbps.
 IP Profile for your line is - 2.71 Mbps

so how come I could get 5/6 mbps 4 years ago on bog standard adsl?

Nick

the acceptable range of speeds is 1.2 Mbps-4 Mbps.

this refers to throughput at your connection speed.

It says nothing about the current sync speed relative to the FTR and you missed the sync speed out of the cut & paste.

Download speedachieved during the test was - 7.13 Mbps
For your connection, the acceptable range of speeds is 0.6 Mbps-7.15 Mbps.
Additional Information:
Your DSL Connection Rate :8.13 Mbps(DOWN-STREAM), 0.45 Mbps(UP-STREAM)
IP Profile for your line is - 7.15 Mbps

In reply to a post by yarwell:

the acceptable range of speeds is 1.2 Mbps-4 Mbps.

this refers to throughput at your connection speed.

It says nothing about the current sync speed relative to the FTR and you missed the sync speed out of the cut & paste.

Download speedachieved during the test was - 7.13 Mbps
For your connection, the acceptable range of speeds is 0.6 Mbps-7.15 Mbps.
Additional Information:
Your DSL Connection Rate :8.13 Mbps(DOWN-STREAM), 0.45 Mbps(UP-STREAM)
IP Profile for your line is - 7.15 Mbps

Phil,

I don't know why you seem to defend why people's adsl connections all of a sudden drop (like the OP's and mine). You see loads of the same thing posted on here, and people get asked to check this, check that, change this, post stats, rewire this, change filters et al. All to no avail.

Something is going on at the other end... not at the user end.

Revisited, here is full page:

1. Best Effort Test: -provides background information.

Download  Speed
2.77 Mbps
 
0 Mbps 4 Mbps
Max Achievable Speed

 Download speedachieved during the test was - 2.77 Mbps
 For your connection, the acceptable range of speeds is 1.2 Mbps-4 Mbps.
 IP Profile for your line is - 2.71 Mbps

2. Upstream Test: -provides background information.

Upload Speed
1 Mbps
 
0 Mbps 0.83 Mbps
Max Achievable Speed

Upload speed achieved during the test was - 1Mbps
 Additional Information:
 Upstream Rate IP profile on your line is - 0.83 Mbps


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Remember, since I first got adsl in 2004? I always had a speed of around 5/6 mbps - always, until something changed (not my end).

Nick