ADSL Max Speed

[castro]

When I do a BT Broadband Performance Test I get a number of results.

IP profile for my Line
DSL Connection Rate Upstream
DSL Connection rate Downstream
Actual IP Throughput Achieved During The Test

My question is about the relationship between the actual recorded speed and the theoretical maximum speed for my line.
If the ISP "Big Pipe" is full and the bandwidth is being squeezed then this will effect the actual download speed.
As far as I can understand this value has nothing to do with the maximum theoretical speed achievable.
Under these circumstances and during the 10 day learning period, how does BT determine the "final" speed setting?

[mirage]

hello castro fancy seeing you here....;)

[castro]

Sort of like home from home. Sort of.

[tboorman]

Hi castro,

The MSR (Maximum Stable Rate) set by BT relates to sync speed rather than IP throughput - a good description of how Max DSL works can be found at http://www.kitz.co.uk/adsl/maxdsl2.htm.

[castro]

Is the synch speed the DSL connection rate?

[tboorman]

Yes, that's it.

[castro]

Having got my head around Synch/DSL Connection Rate levels, which have been consistent at 448/7296, I have a question about the IP throughput as measured by the speed test sites.
Since being connected to ADSL24 last Friday, my speeds have been as low as 830kbps and as high as 5475kbps. They are currently around 4000kbps from a morning high of 5400kbps.
For most of yesterday the speeds were around 2600kbps.
Pings rates have been consistent at 34ms av. for the bbc.
Why is the speed varying so much and is this to be expected?

[tboorman]

What does the BT Broadband Performance Tester show your IP profile as?

A couple of things that could be affecting your speeds:


Entanet's anti-loss tool kicking in when all the capacity on the central you're using has been utilised.
Congestion at your exchange - you can check the status of your exchange at http://usertools.plus.net/exchanges/.

[castro]

BT Performance Tester for my line is 6000kbps.
DSL Connection Rateat 10.00 was 448/7296

The status of the exchange is Green and is always Green whenever I have looked.

[tboorman]

Your IP profile is correct for your sync speed. When you're getting low speeds, what does http://tools.entachoice.org.uk/central.cgi report the expected performance of the central you're connected to as?

[castro]

BT Broadband Tester is now showing:
IP profile: 6000
DSL Connection: 448/7296
Actual IP throughput: 588kbps

Entachoice.
Amber-Almost full
Expected Performance: 7.2Mbs

Local Exchange: Green

[tboorman]

I'd advise waiting until the end of your 10 day training period, and then ask Brian to raise it as a fault if your speed problems persist.

[castro]

Thanks Tim
I will certainly take that advice.
It's just difficult to understand how this speed variation can occur when I can get speeds of 5Mbps+ and all the parameters seem to be ok.

[Robbie]

Hi Castro
Have patience, I know its not easy, but just hang on in there and put up with it for the 10 days. Above all, do not keep re-booting your router, just leave things be for the duration ;)

[cliff]

Enternet have yet to bring Global Switch Central 2 and Telehouse Central 3 pipes online, and as such have balanced the load to cope with the high volume of downloaders. This information was taken at 21:30..sun 4th feb, as you can see Telehouse Central 2 is down to 2mbps (must have the bulk of heavy downloaders so don't reboot router if your not on this pipe).
This problem happens at 22:00 hrs every night and of course the weekends....so if you have 300Gig use it. Hopefully Enternet will get the balance right.

Central Pipe Status
Telehouse Central 1 =
Expected performance 5.7Mbps

Global Switch Central 1 =
Expected performance 4.9Mbps

Telehouse Central 2 =
Expected performance 2Mbps

Global Switch Central 2 =
Expected performance 7.2Mbps

Telehouse Central 3 =
Expected performance 7.2Mbps

[castro]

Day 13 so all should be stable.
Profile is Fixed at 6500kbps
DSL connection rate is 448/7616
I/P throughput at 08:00 was 5445kbps
12:00 was 2776kbps
Local Exchange: Green
Entanet: Telehouse1
Expected Performance: 7.2Mbps

This falling-off of speed appears to be a consistent re-occurrence.
Is this to be expected?

[tboorman]

This doesn't sound right to me. Best get Brian to open a fault with Entanet.

[Realist]

PM me your line number.

Regards,