That makes things more interesting.

the FTTC part is ran by Openreach and nothing to do with Infinity. Just to clear that up. The majority of people are with infinity.

Can you try something the files at http://fuller.zen.co.uk/test/

1. Download a single file
2. Download two or more at the same time

Also visit http://www.dslreports.com/tweaks and let us know the results of the tweaktester

Downloaded one of the 100MBfiles, ~270kB/s
Downloading two at the same time, they both do ~270kB/s

In reference to www.dslreports.com:

4. Notes and Recommendations
Change MTU to 1500 (FAQ #652, #695)
Choose RWIN between 281386 and 750834 (FAQ #586)
If you have GlobalMaxTcpWindowSize registry entry (do a REGEDIT Find) then change it to -1 (decimal)
Please fill in OS field <------- (I have windows 7 and that wasn't an option )
Read the tweak FAQ

Observations:
Good data stream (no/few rexmits)

Observations:
Looking good

Edit:

Did several iterations of the 5-threaded test DL from TBBmeter:

TBB Meter graph

Task Manager graph

Seems very regular to me... starts off at ~10Mbps, then tails off to ~5Mbps every time.

Edited by deleted (Thu 19-Jan-12 12:34:31)

Windows 7 the rwin should automatically adjust, but what did it say you have set new e.g.
Receive Window (RWIN): 56720
Window Scaling: off
Path MTU Discovery: ON
RFC1323 Window Scaling: OFF
RFC1323 Time Stamping: OFF
Selective Acks: ON
MSS requested: 1418
TTL:
(less any hops behind firewall)
132
TTL remaining: 117
TOS flags: none set


270KB/sec as in 2.1Mbps is pretty slow. When you said both do 270KB/sec, you mean a total of 540KB/sec at the same time.

IMPORTANT: Dont go on what Windows reports, the green part of tbbmeter is more accurate.

In reply to a post by MrSaffron:

270KB/sec as in 2.1Mbps is pretty slow. When you said both do 270KB/sec, you mean a total of 540KB/sec at the same time.

Yeah sorry I wasn't clear, both downloads were doing 270ish each, a totalling 540 at the same time.

Just ran that tweaker again:

Receive Window (RWIN): 66456
Window Scaling: 2
Path MTU Discovery: ON
RFC1323 Window Scaling: ON
RFC1323 Time Stamping: OFF
Selective Acks: ON
MSS requested: 1414
TTL:
(less any hops behind firewall)
136
TTL remaining: 119
TOS flags: none set


Also, this time I got:

Observations:
Run a line quality test
loss with large packets shown
Check tweak FAQ

Edited by deleted (Thu 19-Jan-12 12:49:55)

MTU - it recommends 1500 however BT recommend using 1492 for their Infinity service and given the infrastructure, I would have though your ISP would be recommending it to. BT Business hubs actually set the MTU to 1492.

Just finished doing that series of tests, here are the results:

TBB Meter results

This was at 8ish this morning, I'll try it again at peak time.

Sorry to bump this guys but the situation hasn't improved any since my last post. We've been in contact with Zen Internet, and they basically said "run some tests using the BT speed tester, because we can see those results". Which is annoying because the BT speed tester always shows our line as acting perfectly, so they just go "Well everythings fine then!" meanwhile i'm still downloading files at less than 2Mbps, even their own test files.

Is there anything I can say or do to get Zen Internet to take this a little bit more seriously? I hate that we're basically just getting passed off when there's clearly a problem.

Edited by deleted (Mon 30-Jan-12 05:35:03)

If BT Speedtester ok, but multiple thread downloads from ocean.zen.co.uk are bad, then suggestion is an issue in the WBC network or Zen - i.e. nothing to do with FTTC itself