Usenet (nntp) speeds

[#1]

A week ago I raised the following ticket:-
I am on BBYW Option 3 - my expected downstream speeds should, I believe, be as shown at http://www.plus.net/support/broadband/products/archive/bbyw/speed.shtml#Option3speeds
Until very recently that is precisely what I got, result happiness.
Now Usenet (nntp) speeds have collapsed. During the day it is around 120 Kbps in the evening it is 56K modem speed and even at 06.50 it is only 720 Kbps. I do not believe it is congestion at the local exchange since if I do a speed test from e.g. Speedtest.net I invariably get close to my IP profile speed.
Can you please explain?
Yesterday I received the following illuminating response:-
Dear Mr xxxxxx,
Please refer to the expected maximum downstream speeds page below which will detail how your internet activities are rate limited at different times:
http://www.plus.net/support/broadband/products/archive/bbyw/speed.shtml#Option3speeds
Kind regards,
xxxxxx xxxxx
It probably has not escaped the observant reader that there is a certain similarity between the links quoted. Also times when the problem was observed do not, apart from the evening observation, fall within any of the restricted periods.
Has anyone else suffered similar problems or am I alone? I have done download speed tests at various times of the day and from assorted testers and the results are always within a gnat's whisker of my IP profile.
I have now been with PlusNet for a year and this is the first time that there has been any issue with the service. I am very disappointed with the response to my ticket. 

[#2]

This is probably due to a careless contractor digging into the BT tunnel and taking out a load of connections including one 622Mb central.
See this thread http://community.plus.net/forum/index.php/topic,75520.0.html

[#3]

Hi Adagio,
I don't check out the forums very often, only when I have a problem really. I've just come here for probably the same reason in your post; the atrocious nntp speeds over the last few days (that I've noticed - maybe longer)
It's very erratic, I'm currently wavering from a few kBps, peaking at about 150kBps. That's on a maximum speed 8Mb connection that normally can do 800kBps overnight.
Overall, my 12-hour unlimited is down to around 60% of normal capacity. Not good when I've got two weeks of downloads queued up (at the normal download rate).
I think it's unlikely that it's plusnet's fault, or my news provider, newhosting. Download rate does approach it's usual maximum for a short period, between about 4am to 6am - probably when overall internet use is at its lowest.
I know what you mean about your canned response from plusnet though - I recently had similar feelings with being told the obvious, followed by a completely wrong response.
Overall though I have to say that I find plusnet to be the best provider that I have had, and I've tried a few over the years!

[#4]

Current situation is still not back to normal http://usertools.plus.net/status/archive/1239177435.htm

Quote

At approximately 6.00pm last night connectivity was restored to the 622Mbps BT central that we lost when contracters bored through a BT communications tunnel in Ilford on Saturday. This means that we are now back to full capacity, and customers can once again connect to the gateway known as ptn-ag1. Despite connectivity being restored, the network is still out of balance and will continue to be until there are sufficient customers connected to ptn-ag1. For this reason we have taken the decision to continue running the network in 'High Demand Operation'. Whilst in High Demand Operation you may notice that your Internet connection is slower than normal. This will be more noticeable during peak times especially when using low priority services and applications like peer to peer and binary Usenet. As ptn-ag1 is back in service, we're going to mark this issue as resolved. For further details regarding the ongoing issues and the impact on customers these are having, please refer to the 'Broadband capacity & performance problems (56049)' and 'Home Phone service problems (56049)' Service Status threads. Kind Regards, Bob Pullen Customer Support

[#5]

The reason for your speeds is given in the Service Status messages, posted here.
Effectively, Plusnet lost one of their 'Centrals' which connect the customer to their networks.  As a result, they placed the whole network in 'High Demand' mode, (also known as Amber status).  This is a pre-emptive move to ensure that the network will continue to function, by rate-limiting non-interactive services like P2P and usenet.
The full description of High Demand mode is available here.
Hope that helps!
B.

[#6]

@adagio, the fact that you started seeing problems before the BT outage is a little concerning. I've just added some comments to your ticket and returned it to you. I might not find the time to follow it up but hopefully it should nudge things in the right direction.
There are a *lot* of Premier non-interactive drops on some of the gateways at the moment, and there will be until we're back in balance. Chances are we'll do some kicking early tomorrow morning now we've got ptn-ag1 back.
In the interim try and get on one of the quiter gateways if you can.

[#7]

I suspect that I was the victim of a 'double whammy'. The problems of last week seemed to have been cured by re-connecting to a different gateway only for them to re-occur on Saturday - the day of the cable vandalism. All seems well now, I suspect that the cause of the issue from 30th March on is now lost in the mists of time.
My thanks to Bob Pullen who in the end provided a sympathetic, sensible and helpful response to my ticket.