Interleaving

[Steve]

Currently on second  2wire router, previous one lasted five days.When migrated on 22nd Feb,initial profile was 7150k with full sync 8128
Had a bad day on 23rd slow speeds, crc's fec's etc then became interleaved with profile 6500k, stats listed below. I was not interleaved previously had full sync with pipex/Tiscali on datastream and also prior to that with pipex ipstream. I have since removed extension and added filtered faceplate without change in router stats. The connection has been stable interleaved, is it worth a risk having it removed or indeed set to auto? I presume I can have it turned back on again it become unstable again? Looking to improve ping times for sons WOW.

DSL Line (Wire Pair):     Line 1 (inner pair)
Protocol:    G.DMT Annex A
Downstream Rate:    7616 kbps
Upstream Rate:    448 kbps
Channel:    Interleaved
Current Noise Margin:    18.0 dB (Downstream) 28.0 dB (Upstream)
Current Attenuation:    21.3 dB (Downstream) 13.0 dB (Upstream)
Current Output Power:    19.8 dBm (Downstream) 12.4 dBm (Upstream)
DSLAM Vendor Information:    Country: {0xB5} Vendor: {TSTC} Specific: {0x04}
PVC Info:    0/38

[Rik]

Looks like DLM has kicked in and raised your target margin to 15db and your last re-sync was at night, hence lower speed but an 18db margin now.

What is your error count like?

[Steve]

Thanks Rik. Just added replacement 2wire this am so nothing to show at the moment, was using p660hw t1 ver 2 in between which i didnt get on with, as I found the firewall hard to set up and also discover the error count. But it seemed pretty stable with reasonable speeds. I suppose I am suspicious of that first 2 wire router as the cause of the initial problems. Am I still going to see errors whilst interleaving is set on?

[Rik]

If interleaving is on, you'll see FEC errors. On the 2700, they show as corrected errors, eg:

Corrected Blocks:       10135       10135       67       0:00:13

[Inactive]

Thanks Rik. Just added replacement 2wire this am so nothing to show at the moment, was using p660hw t1 ver 2 in between which i didnt get on with, as I found the firewall hard to set up and also discover the error count. But it seemed pretty stable with reasonable speeds. I suppose I am suspicious of that first 2 wire router as the cause of the initial problems. Am I still going to see errors whilst interleaving is set on?

I use that Zyxel, I tried a 2700 with my good lines, the Zyxel performed better than the 2700.

Strange, but true.

[Steve]

So if the FECs stay low it is perhaps worth asking for the interleaving to be turned off? However I did think there was an auto setting so that you can have the best of both worlds? With regard the p660 hw I have not noticed any difference but thats probably my ignorance but I struggle with concept of the firewall rules and which direction the packets are supposed to be going.

[Rik]

Hi Steve

Basically, yes, low FECs means you don't need interleaving. I think the auto setting just works to turn interleaving on if the system feels it's needed. I'm not sure it turns it off again afterwards.

[Steve]

Thanks Rik,Looks like it needs some heavy use over the next few days and see how the stats come out, providing this 2wire doesnt break. I did email Idnet with regard to interleaving and they did suggest that removing it my slow my throughput?

Regards Steve

[Rik]

If interleaving is needed (and they will have looked at your error count), then removing it will slow throughput, as more re-sends will be needed.

[Steve]

Thanks for the help. I will post figures later showing error counts

Regards Steve

[Steve]

I have been using a 585 v 6 now as you can see for seven days and I am undecided whether the error count that has occurred over a total download of 4GB justifies the use of interleaving? Obviously the connection is now stable and fast (ip 7000).Also if I keep this sync for 14 days and then resync and the downstream margin falls could this indicate that I have managed to reduce the noise on my line (fitted filtered face plate) and further justifies having interleaving removed?

xDSL Type                    :  ADSL
xDSL Standard                :  ITU-T G.992.1
xDSL Annex                   :  Annex A
Channel Mode                 :  Interleaved
Uptime (days hh:mm:ss)       :  7 days, 1:53:02
Number of resets             :  1
Total Available Bandwidth           Cells/s           kbit/s
  Downstream                 :     19094             8096
  Upstream                   :      1056              448
Intrinsic/Actual and Maximum Bandwidth %              kbit/s
  Downstream                 :        76            10560
  Upstream                   :        34             1304
Bearer Generic Info               Downstream        Upstream
Margin       (dB)            :        14.5             27.0
Attenuation  (dB)            :        20.0             12.5
OutputPower  (dBm)           :        19.5             11.5
 
Transfer statistics
    Errors
      Received FEC           :      6009
      Received CRC           :        19
      Received HEC           :        17
      Transmitted FEC        :         0
      Transmitted CRC        :         0
      Tranmsitted HEC        :         0
     Near end failures since reset
      Loss of frame          :         0 failures
      Loss of signal         :         0 failures
      Loss of power          :         0 failures
      Errored seconds        :         0 seconds 
     Near end failures last 15 minutes
      Loss of frame          :         0 seconds
      Loss of signal         :         0 seconds
      Loss of power          :         0 seconds
      Errored seconds        :         0 seconds
     Near end failures current day
      Errored seconds        :         0 seconds
     Near end failures previous day
      Errored seconds        :         0 seconds

[Rik]

Hi Steve

I can't see your sync speeds for looking, but you have plenty of headroom on the noise margin, so hopefully will get a reduced target and higher sync speed after 14 days or so. The error count is negligible, ~860/day or a bit over one every two minutes, so it looks like it could be removed providing the line isn't prone to bursts of noise. Do you have any idea of how the errors are distributed?

[Steve]

Sorry Rik. Must have edited sync speeds out.  They are 8096 and 448. I just wonder whether there is any way of collecting error data in real time, so I can see whether I am having a sudden burst of errors at certain times of the day? I had thought initially they occurred when the laptop connected but now not so sure, also not monitored son's use of P2P software and rate of error occurrence? However the last large bursts of errors occurred the night of the BT maintenance and previous to that 2 days after migration on a soon to fail 2wire router,dodgy extension and an unfiltered faceplate

[g7pkf]

with stats like that and that speed i cant see a good reason for interleaving to be on.

I bet you live very near the exchange...

sudden burts of errors sound like electrical interferance from the likes of c/h thermostats, fridges,flourecent lights etc.  a good mains filter and i mean MAINS FILTER not a cheap surge protector (there is a differance one protects one filters-mains filters usually have surge as well) would probarly solve these..

[Rik]

Hi Steve

I don't know of anything which monitors the error count - we'll have to talk nicely to John Own  (Routerstats).

All I can think of is to try and read them every hour during the day, and see when the changes occur.

[Steve]

Rik, I think "ADSLMonitor" software will plot crc's but that is not much use to me as they are infrequent and it would be I think challenging for me "read too lazy as well" to configure it for the 585.I have been using DMT as "telnet interface". So a "refresh" gives me any easy error update.It's odd today the SNRM is sitting rock solid at 14.5db with no deviations at all, normally it varies by 0.5 to 1db on a refresh

g7pkf, Do you place a mains filter on the noisy appliance or with the router. I have one on my hi fi, seem to recall it didnt come cheap,can you suggest?

Thanks

[Steve]

Rik,  RouterStats2.8j Does appear to be able to monitor the FEC count by using the router search text in the configuration menu >get page. highlight "fec count numbers and then assign to user define 1 or 2 tabs .I discovered this as I had to use this method to display the correct sync and snrm values on the speedtouch 585 v6. I have the graph which of course due to sods law is a straight line as I have had no FEC errors lately.

[Rik]

Nice bit of lateral thinking, Steve.

[g7pkf]

normally it varies by 0.5 to 1db on a refresh

g7pkf, Do you place a mains filter on the noisy appliance or with the router. I have one on my hi fi, seem to recall it didnt come cheap,can you suggest?

Thanks

Mine varies by 10dB over 10 second refresh(with a train going by) so 0.5-1 nowt to worry about....cable swinging in the wind

stick it on the router and if poss any connected computer gear as well, as you probarly are not "sure" which piece of equipment is causing the problem...and it may be next door etc, once had a case of a dvd player knocking out 4 yes 4 houses each sides adsl connection (albeit intermittantly), needless to say the neighbours "bought" the offending neighbour a new dvd player--external interferance get onto manufacturer etc etc (easier and cheaper to buy new one)

Quick test is tune radio (in car/portable) to a very weak LW station and drive around (5 live??) i seem to recall is a good choice when you get a load of interferance your near the problem.

Dean