I have asked IDNet to turn Interleaving back ON.

Dont mention Talk Talk !! · Feb 25, 2008, 21:28:30

I had posted before about getting a 2wire hg1800v router as my old DLink 504T router was causing repeated stale sessions . The DLink was connected with interleaving switched ON though it still showed sync`ing at 8128k and IP Profile of 7150k, which was odd because I thought max sync for interleved line was 7616k .

I got the 2wire router and asked IDNet to turn the interleaving OFF and it connected at 8128k with profile of 7150 k , funny thing is though, even though Ive left it for about 2 weeks, my line was faster in the past with Interleaving ON. Ive noticed that with the interleave switched off, my downloads have been significantly slower, circa 400 kb/sc OFF as compared with 750+ kb/sec with interleave ON.

I phoned IDNet today and requested that Interleave be switched back ON and described my scenario to the bloke at support. He said in some instances that an Interleave enabled line can be faster than a non-interleaved one that is sync`ing at the max rate.

Anybody have any knowledge as to what I am describing here ?

James

Lance · Feb 25, 2008, 21:46:43

The reason a interleave enabled line can be faster is because, where needed, it stops so many packets [of data] having to be resent.

For example, say you were downloading a file which was 100 packets longs. On the non interleaved line it may need to ask for 50 packets to be resent due to errors. However, on the error correcting interleaved enabled line it may only need to ask for 25 packets to be resent. Because less packets are having to be resent it will be quicker.

Does that make sense now?

Sebby · Feb 25, 2008, 22:33:27

As Lance says, it's a form of error correction, so if you're on a less-than-perfect line and suffer lots of errors, interleaving will help to reduce them, meaning higher throughput.

Rik · Feb 25, 2008, 23:54:30

Or, put another way, less is sometime more.

Inactive · Feb 26, 2008, 00:37:47

More or less..

Rik · Feb 26, 2008, 00:39:56

Give or take.

LesD · Feb 26, 2008, 21:02:21

How do you know if your line is interleaved?

Syncing at a mere 4288 kbps tonight would interleaving help or hinder me?

Is it a router issue? Maybe my old mkI Netgear DG834 isn't up to this.

Sebby · Feb 26, 2008, 21:06:02

Do you know for sure that you aren't already interleaved, Les? I would guess that you are.

LesD · Feb 26, 2008, 21:12:22

Quote from: LesD on Feb 26, 2008, 21:02:21
How do you know if your line is interleaved?

No Sebby I don't that's why I asked.

A brand new IDNet member told me today that his Linksys router tells him his line is interleaved.
I have routed (like the pun) through my Netgear Router info/setup/stats and cannot see any mention of it.

Sebby · Feb 26, 2008, 21:16:59

How to Check for interleaving (source: Kitz.co.uk)

First logon to the router and then select this address:
http://192.168.0.1/setup.cgi?todo=debug

which should result in a screen which just says 'Debug enable'.
(That's assuming that you haven't changed the router's IP address from the default).

Then exit from the web interface and open a command-line window. Type: telnet 192.168.0.1

You should get a BusyBox welcome message to confirm that your telnet connection is established.

Now type: cat /proc/avalanche/avsar_modem_stats

This will give you a stream of information about the ADSL connection. Scroll up and find a section something like this:

[Upstream (TX) Interleave path]
CRC: 0 FEC: 0 NCD: 1
LCD: 0 HEC: 0

[Downstream (RX) Interleave path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0

[Upstream (TX) Fast path]
CRC: 1 FEC: 68 NCD: 0
LCD: 0 HEC: 0

[Downstream (RX) Fast path]
CRC: 49 FEC: 0 NCD: 0
LCD: 0 HEC: 0

In this example the interleave figures are all zero, apart from the first NCD value, which always seems to be 1, so this router is in fast mode. If you see zeros in the fast path sections and other figures in the interleave sections, then interleave is on.

LesD · Feb 26, 2008, 21:29:30

Hi Sebby,

Thanks for the guidance.

I had never been there before.

This is what I got:

AR7 DSL Modem Statistics:
--------------------------------
[DSL Modem Stats]
US Connection Rate: 448 DS Connection Rate: 4288
DS Line Attenuation: 41 DS Margin: 4
US Line Attenuation: 26 US Margin: 21
US Payload : 12339696 DS Payload: 38969952
US Superframe Cnt : 5995924 DS Superframe Cnt: 5995924
US Transmit Power : 0 DS Transmit Power: 0
LOS errors: 0 SEF errors: 0
Frame mode: 3 Max Frame mode: 0
Trained Path: 1 US Peak Cell Rate: 1056
Trained Mode: 3 Selected Mode: 1
ATUC Vendor Code: 414C4342 ATUC Revision: 1
Hybrid Selected: 1 Trellis: 1
Showtime Count: 1 DS Max Attainable Bit Rate: 4288
BitSwap: 1 US Max Attainable Bit Rate: n/a

[Upstream (TX) Interleave path]
CRC: 22 FEC: 1904 NCD: 0
LCD: 0 HEC: 0

[Downstream (RX) Interleave path]
CRC: 2789 FEC: 455285 NCD: 0
LCD: 0 HEC: 0

[Upstream (TX) Fast path]
CRC: 0 FEC: 0 NCD: 1
LCD: 0 HEC: 0

[Downstream (RX) Fast path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0

[ATM Stats]
[Upstream/TX]
Good Cell Cnt: 257077
Idle Cell Cnt: 107443293

[Downstream/RX)]
Good Cell Cnt: 811874
Idle Cell Cnt: 1030019484
Bad Hec Cell Cnt: 13175
Overflow Dropped Cell Cnt: 0

[SAR AAL5 Stats]
Tx PDU's: 64704
Rx PDU's: 80983
Tx Total Bytes: 9522772
Rx Total Bytes: 36008467
Tx Total Error Counts: 0
Rx Total Error Counts: 7

[OAM Stats]
Near End F5 Loop Back Count: 0
Near End F4 Loop Back Count: 0
Far End F5 Loop Back Count: 0
Far End F4 Loop Back Count: 0
#
#

I guess that I am not interleaved as NCD is 1 in fast mode but I am out of my depth now!

Now how do I turn de-big off again?

Sebby · Feb 26, 2008, 21:37:47

Yep, you're already interleaved. I suspected you were as most lines that can't achieve close to full speed are going to be less-than-perfect, and therefore probably suffer high errors.

I only get about 300k higher sync than you. I bet a 2Wire 2700HG boost your sync enough to get your a 4000k profile like me (sync needs to be 4,544k). It's worth a try if you're potentially looking for a new router, and they can be had for not much at all on eBay. You'll find some threads in the 2-Wire child forum in IDNet Help.

I'm not sure how you disable debug now; Rik will know for sure when he's back. He's a Netgear expert (although he also has a 2Wire now).

LesD · Feb 26, 2008, 21:42:47

OK thanks again for the help. I am still a bit confused but I am sure in time the penny will drop given time!

Sebby · Feb 26, 2008, 21:53:41

Basically, what I'm trying to say is that your sync is not quite enough for a 4000k IP profile, so at the moment you're on a 3500k profile. The 2Wire 2700HG router is well known for its ability to sync higher than most other routers. If you bought one, it would probably let you sync at a rate high enough to give you a 4000k IP profile, then your connection will be a bit faster.

Rik · Feb 26, 2008, 23:30:46

Just to expand on what Sebby has said, Les, it's this section of your stats:

[Upstream (TX) Interleave path]
CRC: 22 FEC: 1904 NCD: 0
LCD: 0 HEC: 0

[Downstream (RX) Interleave path]
CRC: 2789 FEC: 455285 NCD: 0
LCD: 0 HEC: 0

Which tells us you have interleaving on. The FEC errors in the interleave path are the clue.

LesD · Feb 27, 2008, 10:01:41

Quote from: Rik on Feb 26, 2008, 23:30:46
The FEC errors in the interleave path are the clue.

Ah I see, I was thinking it was something to do with the value of zero or one that the NCD parameter took up.

Now I have debug on in my Netgear do you know how to turn it off again or should I just leave it on?

Rik · Feb 27, 2008, 10:03:34

Re-boot the router is the easy way, Les. I think that there's a classier way, but that's what I always did.

LesD · Feb 28, 2008, 21:24:57

Quote from: Rik on Feb 27, 2008, 10:03:34
Re-boot the router is the easy way, Les. I think that there's a classier way, but that's what I always did.

OK done & dusted!