Thread: Max Attainable Line Rate(Down Stream) problem

i 've got a dlink 802c modem and i am on bsnl dataone 500 c

i have an SNR problem .. my SNR is usually below 10 and my exchange people are working on it .....

This is my current status

Vendor ID: 0039
Revision Number: E.37.9.48
Serial Number: 123456789abcdx
Local Tx Power: 11.3 dB
Remote Tx Power: 20.5 dB
Local Line Atten.: 58.5 dB
Remote Line Atten.: 90.0 dB
Local SNR Margin: 11.0 dB
Remote SNR Margin: 6.5 dB
Self Test: Passed
DSL Standard: ADSL2+
Profile: MII
Tx Line Rate: 85 Kbps
Rx Line Rate: 597 Kbps
Max Attainable Line Rate(Down Stream): 628 Kbps



my modem disconnects frequently but reconnects automatically but sometimes after reconnection my speed is reduced drastically to 256 kbps or 128 kbps instead of the regular 1.7 mbps i get ... whats the reason ???

right now the maximum speed as u can see in the status page .. is 628 kbps... and i have to manually restart the modem a few times for the speed to go back to 1.7mbps ...

why's this happening ???


PS - right now my line attenuation is pretty high ..but usually even when my line attenuation rate is in the 50's i get 1.8mbps max download ....

@itsrijo

.I 've got a dlink 802c modem
I am on bsnl dataone 500 c
I have an SNR problem .. my SNR is usually
below 10 and my exchange people are working on it .....
This is my current status
...................................
Local Line Atten.: 58.5 dB
Remote Line Atten.: 90.0 dB
Local SNR Margin: 11.0 dB
Remote SNR Margin: 6.5 dB
Self Test: Passed
DSL Standard: ADSL2+ Uncheck and try GDMT
Profile: MII
Tx Line Rate: 85 Kbps
Rx Line Rate: 597 Kbps
Max Attainable Line Rate(Down Stream): 628 Kbps......

You should be happy that you are still connected to Internet !
Your line conditions are awful !

1.Do you use an ADSL Splitter ahead of Dlink 802 C? ( or builtin? )
2.How you connect telephones in various rooms ? how many ?
3.Change to GDMT only and recheck SNR etc values.
4. Make the shortest connection from BSNL Phone outlet to Modem.
5. Check cables RJ11 and RJ45 for black contacts/oxidization/
6. When connected, test speed at Speedtest.net - The Global Broadband Speed Test.
Select a server say Mumbai or Delhi.
Copy /paste link ( remove http) and post here
or give the data .
Feedback.

As essbebe say set your ADSL mode to G.DMT
You are in 500C plan. G.DMT mode is good for you.
Changing to mode G.DMT will change your Line rate to 2048Kbps and 256Kbps if all settings are good in your exchange.

when i try to change to GDMT

i get this error - Fails to perform the specified action...
Error: Invalid combination of Standard and Annex Type specified

and since i use dlink 802c ..the settings are listed in a dropdown menu .. and not tickboxes like bsnl modem... [ is this a problem ]

so basically my adsl configuration page is like this (i've marked present settings in red)
Annex Mode Config: [automatic , user selected ]
User Selected Annex Mode: [ADSL2 , Annex A ]
Trellis: [enabled . disabled]
Handshake Protocol: [ T1.413 , G.lite , G.dmt , mutimode , adsl2 , adsl2+, re adsl , adsl2 auto, adsl2+auto ]
Bit Swapping: [ enabled , disabled ]



1.Do you use an ADSL Splitter ahead of Dlink 802 C? ( or builtin? )

phone line -> adsl splitter -> modem

2.How you connect telephones in various rooms ? how many ?

i've disconnected all the parallel phones ..right now only 1 phone ... a single wire comes from the junciton box outside to the ADSL splitter ...

3.Change to GDMT only and recheck SNR etc values.

cant change to GDMT

4. Make the shortest connection from BSNL Phone outlet to Modem.

the cable from the phone outlet to the modem is pretty long/old and coiled... maybe 15 or 20 meters

5. Check cables RJ11 and RJ45 for black contacts/oxidization/

i dont see anythng... i'll get new cables anyway ...

6. When connected, test speed at Speedtest.net - The Global Broadband Speed Test.





and these are the paramters right now

Vendor ID: 0039
Revision Number: E.37.9.48
Serial Number: 123456789abcdx
Local Tx Power: 11.3 dB
Remote Tx Power: 20.5 dB
Local Line Atten.: 57.5 dB
Remote Line Atten.: 47.5 dB
Local SNR Margin: 6.5 dB
Remote SNR Margin: 5.5 dB
Self Test: Passed
DSL Standard: ADSL2+
Profile: MII
Tx Line Rate: 82 Kbps
Rx Line Rate: 998 Kbps
Max Attainable Line Rate(Down Stream): 1084 Kbps
SRA Parameters
Auto SRA: Disable
SRA CRC Error Rate: 1800
SRA FEC Error Rate: 60
SRA Up Shift Obs. Period: 3600 Secs
SRA Down Shift Obs. Period: 600 Secs
Power Management Mode: L2, L3 Both Allowed

Annex Mode Config: user selected

In this option have some option or only user selected
If there is only user selected then select this only
User Selected Annex Mode: Should be G.DMT
Handshake Protocol: Should be G.DMT

There is some problem in this model to the changing the Mode of the protocol
other users reported same problem.

IN User Selected Annex Mode ..the options are ANNEX A or ADSL2 .. i've corrected the post....

so indiranil .. should i select annex a or adsl2 .. right now i've changed it to annnex a ..

and guys .. whats the point of changing to GDMT ???

Please download the user manual 1MB

size.
Download QIG&User Manual.zip from Sendspace.com - send
[quote]big files the easy way

select whatever Mod mode selection is available and recheck snr etc.
Adsl2 is GDMT bis.

whats the point of changing to GDMT ???

Usually a more stable connection and modem
synchronises to lower Attainable rate .
ADSL2 + is for very high speed broadband connections.
( Fore speeds upto 2 Mbps GDMT is recommended)
Compare Mine just now changed to GDMT

Mode: ADSL2+
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 34.3 22.5
Attenuation (dB): 20.5 7.1
Output Power (dBm): 10.4 0.2
Attainable Rate (Kbps): 14580 45592
Rate (Kbps): 2047 510

[/B]Mode: G.DMT [B]
Type: Interleave
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 32.6 25.0
Attenuation (dB): 16.0 3.5
Output Power (dBm): 12.3 16.3
Attainable Rate (Kbps): 7648 1024
Rate (Kbps): 2048 512

Note significant drop in Attenuation D/L and U/L



.

can u explain it a bit more ... essbebe .. i dint understand your post completely ....

anyways.. no matter how many times i try to change it to GDMT ... it reverts back to ADSL+2 after restart !!!!

I 've marked present settings required in BLUE)
Annex Mode Config: [automatic , user selected ]
User Selected Annex Mode: [ADSL2 ,[ Annex A ]
Trellis: [enabled . disabled]
Handshake Protocol[: [ T1.413 , G.lite , G.dmt [, UNCHECK mutimode [, adsl2 , adsl2+, re adsl , adsl2 auto, adsl2+auto ]
Bit Swapping: [[enabled , disabled ]
[url]http://i48.tinypic.com/2ntfv28.jpg 34.6 KB

[IMG][SUBMIT wait for two minutes.
NOTE
User manual Not available in Dlink web site.

i changed my ADSL2+ automatic configuration to this :

Annex Mode Config: [ user selected ]
User Selected Annex Mode: [ Annex A ]
Trellis: [enabled ]
Handshake Protocol[: [ G.dmt ]


but after a reboot .. the setting goes back to ..

Annex Mode Config: [automatic ]
User Selected Annex Mode: [ADSL2 ]
Trellis: [enabled ]
Handshake Protocol[ adsl2+auto ]
Bit Swapping: [enabled ]

why does it change back to old settings after reboot ???

After clicking "Submit".
see if you can open ""and click there
SAVE/reboot option.
( I should see manual again !)

yes there was an option to commit and restart and did that now . the settings have changed but the parameter page have also changed now i have more info

DSL Parameters and Status
Vendor ID: 00B5GSPN
Revision Number: E.37.9.48
Serial Number: 123456789abcdx
Local Tx Power: 11.7 dB
Remote Tx Power: 16.4 dB
Local Line Atten.: 59.0 dB
Remote Line Atten.: 31.5 dB
Local SNR Margin: 7.0 dB
Remote SNR Margin: 6.0 dB
Self Test: Passed
DSL Standard: G.dmt
Profile: MII
Tx Line Rate: 192 Kbps
Rx Line Rate: 1056 Kbps Why is the Tx rate so low 192 kbps
Framing Structure: Framing-3
Trellis Coding: Enable
Power Management Mode: L2, L3 Not Allowed



Config Data Up Down
Intrlvd Fast Intrlvd Fast
AS0(kbps): - - 1056 0
AS1(kbps): - - 0 0
LS0(kbps): 192 0 - -
LS1(kbps): 0 0 - -
RValue: 16 0 10 0
SValue: 16 2
DValue: 2 16

Check all cable contacts for blackened contacts/rust/Oxidization. use short cables.
Your Line Attenuation is very bad.
Also SNR just marginal.
Contact CC to check the line.

Usually the U/L rate will be lower.

Line Atten.: 59.0 dB (*less than 30 needed
Remote Line Atten.: 31.5 dB
Local SNR Margin: 7.0 dB (
should increase higher the better
Remote SNR Margin: 6.0 dB ( same as above)

See thread SNR/Attn margins in forum
Broadband How to ....."

they changed my line .. and the connection has improved drastically ..even though the SNR's still 15'nish .. it was 7-9 before.. but i am happy cuz the connection is stable...

but the attenuation rates are still high .. 56.. but i get around 220 KBps during HTTP downloads and 180 KBps max with torrents... so i dont have much to complain


Vendor ID: 00B5GSPN
Revision Number: E.37.9.48
Serial Number: 123456789abcdx
Local Tx Power: 12.4 dB
Remote Tx Power: 16.6 dB
Local Line Atten.: 56.0 dB
Remote Line Atten.: 31.5 dB
Local SNR Margin: 15.5 dB
Remote SNR Margin: 13.0 dB
Self Test: Passed
DSL Standard: G.dmt
Profile: MII
Tx Line Rate: 512 Kbps
Rx Line Rate: 1760 Kbps
Framing Structure: Framing-3
Trellis Coding: Enable
Power Management Mode: L2, L3 Not Allowed


thanks a lot essebe.. you've been the most helpful...