Non-Broadcom Issue...

Sorry if this has been asked or is a "given" for TT LLU based connections but I have scoured the internet as much as I can and cannot find the answer.

I have three or so customers who (in the last 3 months) [I suspect they were llu'd and the problem started] have issues with their internet.

The problem happens in the evenings only, which is strange.
The sync speed, SNR, FEC etc.. rates, packet loss and pings stay 100% the same through the 24 hour period but in the evenings access to most sites becomes impossible or incredibly slow.

Ebay, yahoo, bbc news etc.. suffer from excessive retransmitted packets and stall loading of the pages.
Radiojackie.com and a select few other sites load at full line speed with no issues!

VPNing to TunnelBroker or my own server during these "problem periods" results in full line speed once again to all the affected sites.

The only fix I have found is to swap their DG834Gv3 (non-broadcom), ZyXEL (non-broadcom), ZoomADSL (non-broadcom), Sagem (non-broadcom) routers for a DG834GT or a TG585v7 and magically the problems disappear.
Swap the router back that same evening and the problems reappear.

To me, it is almost like the network is applying a traffic management profile when non-broadcom routers are in use, which really doesn't seem likely.

I am utterly baffled and any help or pointers on what could be causing this would be fantastic, I am fed up of having to supply Broadcom based routers when their old routers (or brand new! non-broadcom based routers) should work.

*footnote: A USB based Connexant adsl modem also seemed to work fine?

Tom - www.mouselike.org

Edited by deleted (Tue 09-Nov-10 19:00:43)

In reply to a post by drsox:

I am utterly baffled and any help or pointers on what could be causing this would be fantastic, I am fed up of having to supply Broadcom based routers when their old routers (or brand new! non-broadcom based routers) should work.

TBH 50% of your post went over my head so i will just kick the tyres for a moment, my connection works fine on my ancient Billion Bipac router and the only time in the last 12 months i have had slow web page loading times was when TT were having DNS issues, I tried both google and open DNS and both worked perfectly, it may be worth trying if you haven't already.

Na, it isn't DNS Looks up the sites fine.. goes to make a connection to the server, manages it.. sends the request for say "bbc.co.uk/news" and some data comes back.. connection stalls and keeps retransmitting etc..

During that "stall" some other select websites (be usegroup site, radiojackie.com) load without issue :| which is why its so confusing :>

Tom - www.mouselike.org

In reply to a post by drsox:

Na, it isn't DNS Looks up the sites fine.. goes to make a connection to the server, manages it.. sends the request for say "bbc.co.uk/news" and some data comes back.. connection stalls and keeps retransmitting etc..

During that "stall" some other select websites (be usegroup site, radiojackie.com) load without issue :| which is why its so confusing :>

Tom - www.mouselike.org

I will post your question in the TT forum with a link someone may be able to help.

Excellent, thanks.
I was unable to post there due to the requirement for phone number, account number etc.. which I don't have.

Tom - www.mouselike.org

In reply to a post by drsox:

Excellent, thanks.
I was unable to post there due to the requirement for phone number, account number etc.. which I don't have.

Tom - www.mouselike.org

Here you go - http://www.talktalkmembers.com/forums/showthread.php...

Be patient as i got the reply below from one of the OCE's last time I posted a question from here in the TT forum -

We do only have a limited presence on external sites.

The issue you have outlined will be picked up in due course. The forum here takes priority in terms of the support given so the timescale for reply on third parties sites is longer. Rest assured however we are allocating time to the external sites, but the same oldest to newest workstream will apply so this issue will be picked up in relevance to the other THink BB threads from TT customers.

.

Edited by Jack_Hackett (Tue 09-Nov-10 20:06:24)

Thanks for the replies over there (the TT forum) so far..

1) DLM: Not sure, but I don't think the exchange is able to tell the MAC of the router until it syncs? so shouldn't be able to apply a different profile at sync-time.

2) All the users are on the same exchange, so possibly congestion as fred sheehan notes.. but then it doesn't explain why different routers work fine during the exact same time periods :\

3) MTUs changed and tested.. that was one of my first thoughts as AOL used to have similar symptoms when on the 'old dsl network' and the 'incorrect' setting of 1500. In this TT case; lowering the MTU seems to make the problem worse.

4) Certainly not the browser, computer or security software. Very, very well tested on many different computers and operating systems :|

5) I am not charging my customers for this time.. Puzzles are my downfall I must get to the bottom of them no matter what time I spend on it, and certainly don't feel right charging the customer for it (especially when the fix is easy, broadcom router on ebay [ex sky dg834gt or any 585v7] is £15 ).
I would love to send my customers here directly but they wouldn't have a clue what or how to explain it and I doubt they would understand the replies.

6) Eventually if I don't get any answers quickly I will go to the effort of finding out the customers details and registering them for the TT forum.. it just seems a bit much at the moment when I wasn't expecting it to be cross-posted by a kind person on the ThinkBroadband Forums.

My only other thought (as I am very well versed in how BE works) is.. is there an INP setting that needs changing. For example on BE some non-broadcom routers sync slower and drop out more unless "Service Profile 20" (which sets INP 2?) is set on the line.

Does this INP change trigger any 'ahar!' moments over on TT?

Tom - www.mouselike.org

Edited by deleted (Wed 10-Nov-10 00:16:30)

what MTU's did you try? Did you send non-fragmented packets?

mine works at 1472 (which i think is 1500 after the 28 bytes header or something) on BE


C:\Users\Mytheroo>ping www.jolt.co.uk -f -l 1472

Pinging jolt.co.uk [84.234.17.86] with 1472 bytes of data:
Reply from 84.234.17.86: bytes=1472 time=40ms TTL=122
Reply from 84.234.17.86: bytes=1472 time=39ms TTL=122
Reply from 84.234.17.86: bytes=1472 time=35ms TTL=122
Reply from 84.234.17.86: bytes=1472 time=36ms TTL=122

Ping statistics for 84.234.17.86:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 35ms, Maximum = 40ms, Average = 37ms

C:\Users\Mytheroo>ping www.jolt.co.uk -f -l 1473

Pinging jolt.co.uk [84.234.17.86] with 1473 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for 84.234.17.86:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

Edited by deleted (Wed 10-Nov-10 05:15:06)

Just to tag on the end to keep it tidy

Since there are no Sync problems or extra line errors and it does work ok through VPN then it does sound more like MTU problems

On the problem connection(s), compare the MTU directly to this site as well as going through the VPN.

http://www.speedguide.net/analyzer.php

i've seen what i believed to be chipset-related issues and the connection was quite unstable, varying Sync and quite a few line errors.

It would be useful to know what you eventually find to be the cause ..

Yep - set the -f flag on ping

Will continue researching and will pop back if I ever find the answer.

Tom - www.mouselike.org