Are BT traffic shaping?

specifically usenet.

I know they say they don't, but bear with me.

I have Infinity 2 via an Asus DSL-AC68U. I think I get close to line speed when downloading large files etc, or NNTP via supernews. Testing just now (Sat AM) I get about 8MB/s on a download and 5MB/s on supernews.

Last month or so, I've noticed that if any NNTP downloads start in the evening hours, the latency on my connection goes up by >1s and web browsing etc becomes pretty much impossible across the whole network.

The router isn't under high load and doesn't show CPU spikes, the Ethernet or wifi networks aren't heavily taxed, and I don't see the same issue when downloading large files in this peak time - so what else could be going on?

I can't think of anything on the local network that would cause this, so I'm starting to wonder if something is going on with BT's network - either intentional (traffic shaping) or saturated in my area - but then why would only NNTP be affected?

Keen to know if anyone else has seen the same before I retry with the HH5, and think about speaking to BT..


DSL stats, in case they are relevant:

ITU G.993.2(VDSL2), G.998.4(G.INP, Downstream only)

SNR 7.5 dB / 15.6 dB
Line Attenuation 5.2 dB / 0.9 dB
Path Mode FastPath / FastPath
Interleave Depth 1 / 1
Data Rate 79998 kbps / 19999 kbps
MAX Rate 103624 / 33395
POWER 12.9 dbm / -4.5 dbm
CRC 0 / 9

You could always try a Glasnost test http://glasnost.mpi-sws.org/bb/glasnost.php

I have run a few of the tests including NNTP and there is no indication that BT is shaping traffic.

Have you tried another news provider to rule out the current one? That could be the problem.

Edit: Giganews have a free trial to test that theory. https://www.giganews.com/signup/

Matt

Edited by uno (Sat 07-May-16 16:04:20)

The OP's problem appears to be in the evenings. Which to me suggests possible congestion. Perhaps only on their VP.

Congestion on only one protocol though? Maybe outside of BT's network but very unlikely to be VP/SVLAN due to that.

If anything, NNTP should be higher/more consistent if multithread.

Matt

Edited by uno (Sun 08-May-16 14:14:17)

Probably best to run a Glasnost Test when the slow-down is happening

That's basically what I was getting at. Running it at 9am isn't going to show anything.

True. But see my comment re the Glasnost test.

In reply to a post by uno:

Congestion on only one protocol though? Maybe outside of BT's network but very unlikely to be VP/SVLAN due to that.

If anything, NNTP should be higher/more consistent if multithread.

The OP isn't reporting a problem on one protocol - and actually fails to tell us what NNTP behaviour is seen.

His report is that "latency increases to 1s" (presumably, but not necessarily, measured by a ping), and that "web browsing etc becomes impossible". NNTP causes this, but we don't know whether it is also a casualty.

To my mind, traffic shaping would be an option if NNTP were running slow, but not other protocols. A shaped NNTP would leave more room on the line for pings and browsing, not less.

In fact, it seems almost the opposite: that congestion exists, and NNTP should be managed, but isn't!

OP:
When the signs of congestion appear, what speed does NNTP run at? What speed are downloads then?

Are you comparing like with like? Is the same machine being used to generate the downloads as creates the NNTP request? Is it the same machine that experiences latency/browsing issues?

Does everything use the same LAN segment? Do you see latency/browsing issues via Ethernet, if the news transfer runs via WiFi? Or vice versa.