Dlink DSL2500u

[agentrfr]

Hi

I have read a lot of good things about these simple and cost effective routers, the only thing i could not find any information about them was if you could adjust the target SNR margins . After spending some time in the CLI ,it is indeed possible - even after speaking to Dlink SA support who claimed that it was not possible on any of the modems ...

Here is a snapshot of the firware and connection speeds before messing around ( i have a very long noisy adls line)

Board ID: 96332
Software Version: RU_1.53
Bootloader (CFE) Version: 1.0.37-8.7
Release Date: Oct. 28, 2009

Downstream Upstream
SNR Margin (dB): 13.4 9.0
Attenuation (dB): 63.5 31.5
Output Power (dBm): 12.4 16.6
Attainable Rate (Kbps): 2400 716
Rate (Kbps): 1024 512


After Chaging the target SNR
adsl Configure –snr 350
Downstream Upstream
SNR Margin (dB): 22.9 9.0
Attenuation (dB): 63.5 31.5
Output Power (dBm): 12.4 16.6
Attainable Rate (Kbps): 864 704
Rate (Kbps): 896 512

interesting Enough my max Attainable Rate can reach 4mb With
adsl Configure –snr 25 , but i doubt the line would be very stable

SNR Margin (dB): 14.1 10.0
Attenuation (dB): 63.5 31.5
Output Power (dBm): 12.2 10.3
Attainable Rate (Kbps): 4064 712
Rate (Kbps): 1024 512

Also to note , This Small router is holding the line much better than my netgear dg384 v5 , The netgear's noise margin hangs around 6-9db and spikes anything up to -9

All in all , bang for buck id say this little router is a winner ( i paid R210 for mine )

For the love of all things electronic, someone tell me how to set the target SNR margin.

[Pada]

For the love of all things electronic, someone tell me how to set the target SNR margin.

You cannot do that with the D-Link modem - or at least not via the web page.

Why do you want to set the target SNR margin?

If you want a certain target, call Telkom to downgrade your line until that target is reached...

[agentrfr]

I've figured out how to telnet into the device, but it doesnt respond to "adsl Configure –snr 350 ". Am I going to have to muck about in the firmware?

You cannot do that with the D-Link modem - or at least not via the web page.

Why do you want to set the target SNR margin?

If you want a certain target, call Telkom to downgrade your line until that target is reached...

My router can connect stably at 3300kbps, with an SNR of 6.5ish. But sometimes it just connects at say 2800kbps, with an SNR of 8 or 9. I want to try force it to go to 6-7ish to have the line go as fast as possible.

Telkom don't set target SNRs on their exchanges, the exchanges accept whatever the adsl router sends them.

[Soul Assassin]

It's -- not just –

adsl configure --snr 350

[agentrfr]

It's -- not just –

adsl configure --snr 350

Where do I type that? In the telnet prompt?

[Pada]

agentfr:
Where did you get that command in the first place? It looks like its a command for the Billion ADSL modems.

On the D-Link DSL-2500U modem of mine, I can execute the following commands:

> help

?
help
logout
reboot
adsl
atm
brctl
cat
ddns
df
dumpcfg
echo
ifconfig
kill
arp
defaultgateway
dhcpserver
dns
lan
passwd
ppp
remoteaccess
restoredefault
route
save
swversion
wan
ping
ps
pwd
sntp
sysinfo
tftp

And "adsl" command takes the following arguments:

Usage: adsl start [--up] [--mod <a|d|l|t|2|p|e|m>] [--lpair <(i)nner|(o)uter>]
           [--trellis <on|off>] [--snr <snrQ4>] [--bitswap <on|off>] [--sesdrop <on|off>] [--sra <on|off>]
           [--CoMinMgn <on|off>] [--i24k <on|off>] [--phyReXmt  <on|off>]
       adsl stop
       adsl connection [--up] [--down] [--loopback] [--reverb]
           [--medley] [--noretrain] [--L3] [--diagmode] [--L0]
           [--tones <xmtStart xmtNum xmtMap rcvStart rcvNum rcvMap>]
       adsl configure [--mod <a|d|l|t|2|p|e|m>] [--lpair <(i)nner|(o)uter>]
           [--trellis <on|off>] [--snr <snrQ4>] [--bitswap <on|off>] [--sesdrop <on|off>] [--sra <on|off>]
           [--CoMinMgn <on|off>] [--i24k <on|off>] [--phyReXmt  <on|off>]
       adsl bert [--start <#seconds>] [--stop] [--show]
       adsl info [--state] [--show] [--stats] [--SNR] [--QLN] [--Hlog] [--Hlin] [--HlinS] [--Bits] [--linediag] 
           [--reset] [--vendor] [--cfg]
       adsl --version
       adsl --help

If your ADSL modem's switching between speeds like that, then I'd suggest that you just leave it, or rather phone Telkom to downgrade you to 2Mbps where your ADSL connection would be stable, rather than unstable but slightly faster.

[agentrfr]

agentfr:
Where did you get that command in the first place? It looks like its a command for the Billion ADSL modems.

On the D-Link DSL-2500U modem of mine, I can execute the following commands:
If your ADSL modem's switching between speeds like that, then I'd suggest that you just leave it, or rather phone Telkom to downgrade you to 2Mbps where your ADSL connection would be stable, rather than unstable but slightly faster.

I'm running next to the latest firmware, and this is the telnet menu I get. Would you mind telling me your firmware version?

Login: admin
Password:
NAME=DSL-2500U
VERSION=1.0.49
BUILDTIME=Tue Oct 11 12:37:30 MSD 2011
VENDOR=D-Link Russia
BUGS=<support@dlink.ru>
SUMMARY=Root filesystem image for DSL-2500U
BOARDID=96332
For help, type 'help' or '?'.
DSL-2500U# help
Usage:
        Common commands:
                reboot
                save
                reset
                restore http://192.168.62.2/configs/config.xml
                backup http://192.168.62.2/configs/config.xml
                upgrade http://www.dlink.ru/firmvares/firmware.img
                fwversion
                sh
                ps
                ifconfig
                exit
                help|?

        For special commands, see special help:
                show
                create
                set
                remove

        or:
                wan
                lan
                vservers
                raccess
                ipfilter
                urlfilter
                routing
                dhcp
                ddns
                dmz
                upnp
DSL-2500U#

When I try adsl help, I get this:

DSL-2500U# adsl help
Syntax incorrect, type 'help' or '?'
DSL-2500U#

[Pada]

I'm running:
Software Version: RU_1.53

I can't tell you what hardware revision it is, because I don't have physical access to that modem at this moment.

Why don't you just drop this whole attempt at changing the SNR target? THe odds of doing it on the D-Link ADSL modems are slim to none in any case.

[agentrfr]

I'm running:
Software Version: RU_1.53

I can't tell you what hardware revision it is, because I don't have physical access to that modem at this moment.

Why don't you just drop this whole attempt at changing the SNR target? THe odds of doing it on the D-Link ADSL modems are slim to none in any case.

It cost me R140, and I like to fiddle

Could you perchance login to the router's stats page and quote the firmware version that is currently running? I am also running software version RU_1.53, but I am running firmware version 1.0.49, hardware model D4

[HavocXphere]

I knew that the D-Link has a CLI where you can add routes, dial PPPoE connections, etc., but I never knew that you can set a target SNR margin!

Why don't you just drop this whole attempt at changing the SNR target? THe odds of doing it on the D-Link ADSL modems are slim to none in any case.

OK I'm seriously confused.

[Pada]

All I can find is:
Bootloader (CFE) Version: 1.0.37-8.7

[Pada]

OK I'm seriously confused.

Hehe. I probably should've read this thread again

If I just carefully read what I posted today, I would've seen that I can actually change the SNR target with:

adsl configure --snr <snrQ4>

!

[Pada]

I now actually played with that command and it actually made quite a difference!

When I set it to 'snr 200' (target SNR = 12dB) it changed the modulation to ADSL2+, even though I've only selected G.DMT modulation.
Now I set it to 'snr 230' (target SNR = 13.8dB), it changed the modulation to ADSL2.

Currently my stats are (down/up):
Modulation: ADSL2
SNR Margin (dB): 14.6 / 12.9
Attenuation (dB): 37.0 /17.8
Output Power (dBm): 3.0 / 0.0
Rate (Kbps): 2048 / 507

My ADSL profile is locked at 2Mbps with Telkom, because my connection was unstable otherwise.
I'll play around with higher target SNR values than 13.8 when I have physical access to the modem again.

I'm just guessing that I have the correct translation between snrQ4 and the actual SNR target.
How I have it is:
snrQ4 = Target SNR / 6dB * 100. eg. snrQ4 = 13.8dB / 6dB * 100 = 230
Target SNR = snrQ4 / 100 * 6dB. eg. Target SNR = 230 / 100 * 6dB = 13.8dB

[agentrfr]

I now actually played with that command and it actually made quite a difference!

When I set it to 'snr 200' (target SNR = 12dB) it changed the modulation to ADSL2+, even though I've only selected G.DMT modulation.
Now I set it to 'snr 230' (target SNR = 13.8dB), it changed the modulation to ADSL2.

Currently my stats are (down/up):
Modulation: ADSL2
SNR Margin (dB): 14.6 / 12.9
Attenuation (dB): 37.0 /17.8
Output Power (dBm): 3.0 / 0.0
Rate (Kbps): 2048 / 507

My ADSL profile is locked at 2Mbps with Telkom, because my connection was unstable otherwise.
I'll play around with higher target SNR values than 13.8 when I have physical access to the modem again.

I'm just guessing that I have the correct translation between snrQ4 and the actual SNR target.
How I have it is:
snrQ4 = Target SNR / 6dB * 100. eg. snrQ4 = 13.8dB / 6dB * 100 = 230
Target SNR = snrQ4 / 100 * 6dB. eg. Target SNR = 230 / 100 * 6dB = 13.8dB

Interesting. It is weird that the newer firmware doesn't have the adsl arguments in the telnet. I've just managed to convince my one to synch at 3323 Kbps.

Next time you get, would you mind typing your hardware revision and build date? It's really weird, but I think you are on the 2500u BRU D series board with the 1.53 software set, build date 11 12 2009. That is what the bottom sticker on my one says, but I have since flashed it to 1.0.43, which as far as I can work out, is specific to the D4 model... I wish they put this documentation in English :/

Anywho, on a different note, your attenuation is only 37. You should easily be able to do 6 meg or more. I have 59ish dB of attenuationa and I'm synching fine at 3.3meg, no packet loss, no stability issues.

Parameter
	
Up
	Down
Rate	851 Kbps	3323 Kbps
Attainable rate	860 Kbps	3748 Kbps
SNR Margin	5.7 dB	4.9 dB
Attenuation	36.7 dB	59.0 dB
Output Power	0.0 dBm	12.7 dBm