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Broadband Related => Broadband Technology => Topic started by: snadge on May 02, 2012, 01:41:55 PM

Title: help using switches on telnet
Post by: snadge on May 02, 2012, 01:41:55 PM
Iam fiddling with DMT Tool telnet, I have read somewhere that the i24k switch helps with stability/errors (whether or not thats true I dont know) - as its not an option in my Netgear GT (DGteam) then Iam trying to enable it va telnet on DMT Tool but I dont know how too?

iam trying

adslctl start --i24k on

is this correct?

thanks
Title: Re: help using switches on telnet
Post by: roseway on May 02, 2012, 04:01:31 PM
That would be the correct command (if it's supported in that version of the firmware). But information on the i24k switch seems to be rather hard to come by, so I don't know if it will do anything.
Title: Re: help using switches on telnet
Post by: snadge on May 02, 2012, 08:21:07 PM
thanks again Roseway.. :)

I know when I enabled sesdrop...thats exactly what happened hehe (Session dropped) and it resynced
Title: Re: help using switches on telnet
Post by: asbokid on May 02, 2012, 08:55:58 PM
Iam fiddling with DMT Tool telnet, I have read somewhere that the i24k switch helps with stability/errors (whether or not thats true I dont know) - as its not an option in my Netgear GT (DGteam) then Iam trying to enable it va telnet on DMT Tool but I dont know how too?

iam trying

adslctl start --i24k on

is this correct?

thanks

No one has discovered the source code for adslctl to confirm for sure.  However, the source code for Broadcom's ADSL driver is available. This reveals that the i24k switch is used to increase the interleaving memory from the default of 16kbyte to 24kbyte.  The idea is that more interleaving memory will cause the errored bits from impulse noise to be spread out more thinly.  Increased interleaving improves the chances that the Reed Solomon decoder will be able to correct more errored bits.  The RS decoder can only correct 'n' bits in error per data block.  And 'n' is determined here by the number of redundant bits that are allocated in a data block to error correction.  Greater interleaving spreads those errored bits across more data blocks, and the RS decoder can in theory correct more bits.

cheers, a
Title: Re: help using switches on telnet
Post by: snadge on May 02, 2012, 09:14:18 PM
ah haa - thanks for that asbokid, i read something about that on broadcoms phyre paper, so it would be good to use especially when using 3db SNRM :)


edit: does it stay between reboots/resyncs..?

edit2: when i enable it, it forces a resync at the default SNRM (it must have been that and not sesdrop that caused the dropout before) , is there a switch to check if its enabled? - what is sesdrop?

thanks for letn me pick your brain asbokid :)
Title: Re: help using switches on telnet
Post by: asbokid on May 02, 2012, 09:39:45 PM
ah haa - thanks for that asbokid, i read something about that on broadcoms phyre paper, so it would be good to use especially when using 3db SNRM :)

edit: does it stay between reboots/resyncs..?

edit2: when i enable it, it forces a resync at the default SNRM (it must have been that and not sesdrop that caused the dropout before) , is there a switch to check if its enabled? - what is sesdrop?

thanks for letn me pick your brain asbokid :)

Hi, snadge.

Is this the Broadcom white paper (on IPTV)?  [1]

Sorry, don't know the answers to either question :-(  Although it makes sense that modifying the interleaving buffer size and depth would force a re-sync.

The --i24k switch for a 24kbyte interleaving memory buffer is probably a proprietary Broadcom extension to xDSL, so it would need a compatible (Broadcom) DSLAM to function.

sesdrop..  Speculating here but maybe it's the number of Severely Errored Seconds before the sync is dropped?

The source code for Broadcom's xDSL kernel driver is here.. [2]   Absent the source code for xdslcmd, that's about the best place for answers..

A few months ago, kitz contributor, JustAnother a.k.a. OmegaPhil a.k.a. OmegaWeapon did a very useful study of all the weird and wonderful switches to the [xdslcmd | adslctl l adslcfg] tool. [3]

cheers, a

[1] http://www.broadcom.com/collateral/wp/XDSL-WP101-R.pdf
[2] http://huaweihg612hacking.wordpress.com/2011/07/26/broadcom-drivers-source-code/
[3] http://forum.kitz.co.uk/index.php/topic,10289.msg
Title: Re: help using switches on telnet
Post by: snadge on May 02, 2012, 10:04:02 PM
hey thanks for those asbokid :)

I dunno about browsing through source code tho...im not that clever hehe, will take a look at the links anyhoo - yeah it was the IPTV paper I was reading and I read something about 16k/24k interleaving but I just skipped through it whilst trying to learn about PhYre

thanks again for the help :)

P.S. I aint heard from sky rep for a few days... perhaps he is off, I am busy printing out a complaint letter too sky to send off tomorrow.
Title: Re: help using switches on telnet
Post by: asbokid on May 03, 2012, 01:22:32 AM
hey thanks for those asbokid :)

I dunno about browsing through source code tho...im not that clever hehe, will take a look at the links anyhoo - yeah it was the IPTV paper I was reading and I read something about 16k/24k interleaving but I just skipped through it whilst trying to learn about PhYre

thanks again for the help :)

P.S. I aint heard from sky rep for a few days... perhaps he is off, I am busy printing out a complaint letter too sky to send off tomorrow.

nothing very clever about it! i just grep the source code with sensible search strings..   wish i had some useful suggestions but i don't (other than be patient and wait for FTTC to reach your area!)

cheers, a
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 02:39:36 PM
@ asbokid - sesdrop = Enabling this option, it will be possible to reduce/eliminate transmission controls and error corrections on data packets, trying to reduce latency in particular on "Interleaved" path ADSL line. It's recommended not to use this option, because many unwanted reliability issues may occur, but if you have excellent line values, you can try to see its effects.
Selecting: default, the router will use ISP predefined setting, normally disabled.
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 05, 2012, 04:10:13 PM
adslctl start --i24k on

is this correct?

It should be "adslctl configure --i24k on". That's what I use anyway :) .

Edit: "adslctl start --i24k on" should work as well.
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 04:19:12 PM
adslctl start --i24k on

is this correct?

It should be "adslctl configure --i24k on". That's what I use anyway :) .

Edit: "adslctl start --i24k on" should work as well.

yeah I found both done same thing...  ive also found sesdrop and i24k are 2 different switches..they could still be used together or something? wish there was more info on this , AND , wish i could enabled it whilst enabling SNRM tweak / phyre and sesdrop
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 05, 2012, 05:43:03 PM
wish i could enabled it whilst enabling SNRM tweak / phyre and sesdrop

You/one can. Just enter adslctl configure --snr WHATEVERVALUE --i24k on --phyReXmt on --sesdrop on.
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 05:50:18 PM
wish i could enabled it whilst enabling SNRM tweak / phyre and sesdrop

You/one can. Just enter adslctl configure --snr WHATEVERVALUE --i24k on --phyReXmt on --sesdrop on.

thanks :)

what are the values to get percentages on SNR..?  7db is my default.. say I want 50% or 35%

thanks
Title: Re: help using switches on telnet
Post by: asbokid on June 05, 2012, 06:13:04 PM
@ asbokid - sesdrop = Enabling this option, it will be possible to reduce/eliminate transmission controls and error corrections on data packets, trying to reduce latency in particular on "Interleaved" path ADSL line. It's recommended not to use this option, because many unwanted reliability issues may occur, but if you have excellent line values, you can try to see its effects.
Selecting: default, the router will use ISP predefined setting, normally disabled.


Aha!  Good find, Snadge! Though not sure I'm brave enough to try it!

As for the reconnect script in the DGTeam software, is it expecting the name of a proper shell script rather than just a single shell command? A shell script means multiple commands could be run.

cheers, a
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 06:44:40 PM
I think so asbo because single line executions dont work?

do you know what to enter for SNR values as mentioned above?  if i want 35% of the TSNRM what do I enter as the value?
Title: Re: help using switches on telnet
Post by: roseway on June 05, 2012, 07:06:55 PM
Typical values are in the table here: http://wiki.kitz.co.uk/index.php?title=Broadcom_CLI#CLI_commands_for_Broadcom-based_routers
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 07:18:01 PM
Typical values are in the table here: http://wiki.kitz.co.uk/index.php?title=Broadcom_CLI#CLI_commands_for_Broadcom-based_routers

thanks Eric :)

so basically if I wasn 3db and my Target is 7db I would use something like 45
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 07:23:18 PM
worked a charm...thanks eric and especially arobertson545 (im gunna name you AR for short lol..too long too type)

adslctl configure --snr 40 --i24k on --phyReXmt on --sesdrop on

it re-sync'd with 3.7db SNRM and my sync at 17.9Mb :)

i will monitor my stats

alls need now is to be able to included that into the BOOT up and RESYNC scripts so It does it without my intervention :)
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 05, 2012, 08:09:24 PM
(im gunna name you AR for short lol..too long too type)

I was wondering when somebody might :) . Anybody who wants to, feel free to call me AR. You are very welcome snadge.
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 05, 2012, 08:11:40 PM
snadge, out of interest, how many error seconds do you usually get per hour?
Title: Re: help using switches on telnet
Post by: snadge on June 05, 2012, 08:19:07 PM
snadge, out of interest, how many error seconds do you usually get per hour?

none... well maybe 2 or 3 or something? is that good?  I have been having lots of reboots and even had margin down to 1.6db for a short while - my last 1 hour on DMT Tool shows about 3 or 4 but last 24 hours = 56 so thats about 2 per hour, but like I say its been up & down
Title: Re: help using switches on telnet
Post by: Bald_Eagle1 on June 05, 2012, 08:31:02 PM
(im gunna name you AR for short lol..too long too type)

I was wondering when somebody might :) . Anybody who wants to, feel free to call me AR. You are very welcome snadge.


@ snadge,
I don't mind if you continue to call me BA either, although I'm not sure what the 'A' stands for. ???
Title: Re: help using switches on telnet
Post by: asbokid on June 09, 2012, 04:34:40 AM
I think so asbo because single line executions dont work?

Single line executions?

What happens if you write a shell script..

Code: [Select]
#!/bin/sh
blahblah commands

save the script under the name myscript.sh to the ramdisk volume, mounted under /var or /tmp or wherever
set its executable bit with chmod +x myscript.sh
and then using the DGTeam configuration tool set it so that the script invokes on re-connects
if the tool lets you run a binary like adslcmd it should let you execute a shell script too

Quote
do you know what to enter for SNR values as mentioned above?  if i want 35% of the TSNRM what do I enter as the value?

Just 35% of what it was before?  I'm not sure I'm so brave  :blush:

Below the Target SNRM is re-adjusted to 60% of its former value..

Before......

Code: [Select]
# xdslcmd info --show
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1196 Kbps, Downstream rate = 19352 Kbps
Path: 0, Upstream rate = 1020 Kbps, Downstream rate = 17223 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.4 12.0
Attn(dB): 19.0 9.7
Pwr(dBm): 20.8 12.1

Code: [Select]
# xdslcmd configure --snr 60
xdslCtl_GetVersion success

[..resyncs..]

Afterwards......

Code: [Select]
# xdslcmd info --show
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1188 Kbps, Downstream rate = 20716 Kbps
Path: 0, Upstream rate = 1020 Kbps, Downstream rate = 18774 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 3.8 11.3
Attn(dB): 19.0 9.8
Pwr(dBm): 20.8 11.8

Another 1.5Mbps is squeezed out of the (TalkTalk LLU) line, but at the expense of a soaring error count..

cheers, a

EDIT:

oh what the heck.. so this is 35% of 60% of the original TSNRM..  Not bad for a 1000 metre local loop...

Code: [Select]
# xdslcmd configure --snr 35
xdslCtl_GetVersion success

[..resyncs..]

Code: [Select]
# xdslcmd info --show
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1200 Kbps, Downstream rate = 21696 Kbps
Path: 0, Upstream rate = 1020 Kbps, Downstream rate = 19944 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 2.3 12.0
Attn(dB): 18.5 9.7
Pwr(dBm): 0.0 12.3
ADSL2 framing
Path 0
MSGc: 59 10
B: 123 145
M: 2 1
T: 5 1
R: 6 0
S: 0.3972 4.5447
L: 5115 257
D: 64 1
Counters
Path 0
SF: 8996 7989
SFErr: 0 0
RS: 1461578 0
RSCorr: 13232 0
RSUnCorr: 0 0

Title: Re: help using switches on telnet
Post by: Bald_Eagle1 on June 09, 2012, 09:10:23 AM
Just as an experiment & for general info, I tried that on my HG612 again (using a value of 60).

It caused an "on the fly" resync, too quick to be detected by Plusnet, therefore a new PPP session was not initiated.

Code: [Select]

Before:
DS Sync US Sync DS SNRM US SNRM DS Power US Power  DS Attain  US Attain
 28377 4895 6.8 6.4 12.4   6.3     34260 5012

After:
DS Sync US Sync DS SNRM US SNRM DS Power US Power  DS Attain  US Attain
 29319 5010 6.3 6.0 12.6   6.3     34660       5017


So it appears that SNRM cannot be adjusted by the user on a VDSL2 connection.

The slight increase in speeds must be simply down to conditions being "quieter" this morning than they were when the connection resynced at around 22:30 last night (for no apparent reason).

That's a shame because now my connection "seems" to be quite stable with low(ish) error counts, SNRM hardly fluctuates at all so I'm sure I could manage on 3dB, thus achieving higher speeds.

Title: Re: help using switches on telnet
Post by: snadge on June 11, 2012, 04:54:17 PM
@ BE - sorry BE... dunno where i got BA from haha  :-[

yeah on 3db SNRM you should get quite a gain on VDSL2, on ADSL2+ when using all tones across the 477 tones its about 2Mbps gain when reducing from 6db to 3db, so you could work out a rough estimation of what you would get from how many tones you currently use - ive since worked out the figure you enter is a percentage of the TSNRM - so entering 50 will attempt to acheive 3db SNRM (if your TSNRM is 6db) - im using 35 at moment and my TSNRM is 7db, im ending up with about 3.1db - it never gets it dead on but near enough..

@ asbokid - the DGteam firmware allows scripts in text to be copy/pasted into a window where you can save them, one for router startup, one for reconnects, one for firewall, one for wifi...etc - oh an BTW if you enter 50 for 50% of SNRM then enter 50% again after doing it once; it isnt 50% of 50% of TSNRM that you end up with, its always the percentage of the TSNRM set by the ISP, not a percentage of your 'current' SNRM... in other words always 50% of 6db...well it seems so in my experience...

so what should I enter in these script boxes if I want to invoke an adsl configure command>?

this is what it says about ROUTER STARTUP

Quote
Router Startup (boot) custom script execution

Here it's possible to add a user defined script which will be executed at the end of the router's predefined startup sequence.
Note: The custom boot script will be executed once and only once in router's OS cycle lifetime and router's ADSL connection must be considered off at script execution: for these reasons, during the script preparation, don't include commands which depend on ADSL connection because they should be better included into the ADSL (re)connection custom script.

Click: Create/Edit Script to create/modify the related script content (a new edit web page will be opened).

    Fill the textbox with your own script content.
    Click Apply to update script content.
    Click Cancel to return to the previous page.

Note: the script won't be run until the related router's OS event occurs.

Click: Delete Script to remove all the related script content (script execution will also be disabled).
Note: router should be rebooted manually to remove script effects.

Click: Execute Script to run the related script immediately (overriding related enable/disable status flag).


this is what it says about RECONNECTIONS

Quote
Router ADSL (re)connection custom script execution

Here it's possible to add a user defined script which will be executed at the end of the router's ADSL connection sequence or whenever a reconnection is needed.
Note: The custom reconnection script will be executed every time an ADSL reconnection event occurs and router's ADSL connection must be considered on at script execution: for these reasons, during the script preparation, it's always recommended to consider command restart events (kill then run) to prevent double executions.

Click: Create/Edit Script to create/modify the related script content (a new edit web page will be opened).

    Fill the textbox with your own script content.
    Click Apply to update script content.
    Click Cancel to return to the previous page.

Note: the script won't be run until the related router's OS event occurs.

Click: Delete Script to remove all the related script content (script execution will also be disabled).
Note: script effects should be removed manually.

Click: Execute Script to run the related script immediately (overriding related enable/disable status fla

ETC ETC
Title: Re: help using switches on telnet
Post by: asbokid on June 11, 2012, 05:28:47 PM
@ asbokid - the DGteam firmware allows scripts in text to be copy/pasted into a window where you can save them, one for router startup, one for reconnects, one for firewall, one for wifi...etc - oh an BTW if you enter 50 for 50% of SNRM then enter 50% again after doing it once; it isnt 50% of 50% of TSNRM that you end up with, its always the percentage of the TSNRM set by the ISP, not a percentage of your 'current' SNRM... in other words always 50% of 6db...well it seems so in my experience...

Sure. I was thinking that it looked wrong: 35% of 60% of 6dB would have been 1.26dB! 

Quote
so what should I enter in these script boxes if I want to invoke an adsl configure command>?

this is what it says about ROUTER STARTUP

Router Startup (boot) custom script execution

Here it's possible to add a user defined script which will be executed at the end of the router's predefined startup sequence.
Note: The custom boot script will be executed once and only once in router's OS cycle lifetime and router's ADSL connection must be considered off at script execution: for these reasons, during the script preparation, don't include commands which depend on ADSL connection because they should be better included into the ADSL (re)connection custom script.

I guess it depends on what the adsl configure command contains.  If it does something that's going to force a re-sync - like change the interleaving memory size - then the command will have to go in a boot script, otherwise the modem would go into an infinite loop of re-syncing.

As for the script, I've never used DG firmware, but would guess that it's expecting a Linux shell script,  which should be of the form

Code: [Select]
#!/bin/sh
command1 (e.g. adslcmd blahblah)
command2
command3

To check that the script is being executed correctly, maybe temporarily tag a line like the following to the end of the script:

Code: [Select]
echo "boot/reconn script successfully executed" > /var/tmp/chkscript.txt

And then manually check that the file has been correctly created..

cheers, a

Title: Re: help using switches on telnet
Post by: snadge on June 11, 2012, 05:44:27 PM
so it would be

#!/bin/sh
adslctl configure --snr 40 --i24k on --phyReXmt on
echo "boot/reconn script successfully executed" > /var/tmp/chkscript.txt


how do I check the chkscript.txt file?

thanks
Title: Re: help using switches on telnet
Post by: asbokid on June 11, 2012, 07:07:33 PM
so it would be

#!/bin/sh
adslctl configure --snr 40 --i24k on --phyReXmt on
echo "boot/reconn script successfully executed" > /var/tmp/chkscript.txt


how do I check the chkscript.txt file?

thanks

just with the cat command.. a la..

Code: [Select]
cat /var/tmp/chkscript.txt

You could do something like echo a timestamp into the file, and use a double >> so that a new timestamp is appended every time the script runs (but that would only be useful for the reconn script.)

cheers, a
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 12, 2012, 06:11:40 PM
You probably knew this, but according to my Broadcom app, i24k is "24 kBytes Interleaving".
Title: Re: help using switches on telnet
Post by: snadge on June 13, 2012, 01:17:16 AM
I aint had time to try these scripts.. will try at weekend as im busy, i got 60 emails in inbox!! bah humbug...like work gathering up lol..

what is this broadcom app your using AR545..?

i24k (Interleaving 24Kbytes)
Title: Re: help using switches on telnet
Post by: GigabitEthernet on June 17, 2012, 08:23:58 AM
what is this broadcom app your using AR545..?

Information and a download link can be found here (http://forum.kitz.co.uk/index.php/topic,11293.0.html).


Sorry for the late response.