I think the SNR bit is slightly misleading.

6dB SNR is an acceptable figure as long as you have a relatively stable line (read: low attenuation) that is free from interference and isn't too far from the exchange.

Depending on how the DSLAM is configured, in most cases the modem and/or DSLAM can negotiate a target SNR by adjusting the sync speed. Assuming your line had a theoretical maximum of 4096Kbps, the closer your sync speed is to 4096Kbps, the lower your SNR is. The issue is that SNR figures can fluctuate throughout different times of the day, based on different external factors etc., hence if your SNR fluctuates excessively, you lose sync.

Say during the day you were able to sync at 3.8Mbit, and your modem reported a SNR (applies to both down/upstream) of 10dB. During the wee hours of the night, condensation sets in which causes your SNR to drop and your modem to lose sync. The modem attempts to re-sync, but this time it can only manage 2Mbps to maintain a SNR of 10dB.

This is why a higher SNR will give you more headroom.

A number of Australian ISPs allow users to change the configuration profile to tweak the target SNRs from the DSLAM side as well as turn interleaving on/off to maximize your sync rate and minimize latency. Most DSLAMs will, however enforce a 10dB SNR. AFAIK, the quickest profile for sync speeds at the moment will enforce a SNR of 6dB both up and downstream, with interleaving turned on.

This profile works for most people; however if you have line issues, electrolysis, a distance of over 3-4KM from the exchange etc, you will need to pick a profile that allows you more SNR headroom.

If you have an extremely poor line, it is possible that you may not be able to sync at the target SNR. In this situation your sync speeds will generally be low (usually under 1Mbps) and you will experience a large number of dropouts.

I wouldn't know if TM Nut techs actually tweak SNR settings on the DSLAM side, but certain modems (ie. Billion, don't think they're sold in Malaysia) offer users the ability to change Coding Gain and Tx attenuation settings to tweak sync speeds. This may or may not alter your SNR - your mileage may vary.

PS. I'm not sure about Malaysia, but as I mentioned earlier the majority of Australian DSLAMs are set to achieve a target SNR of 10dB, with sync speeds uncapped. If your line is capable if a sync speed of 8Mbps but you are only connected at 4Mbps due to your plan being capped, you could very well have a SNR of over 20dB. This does not necessarily make your connection any more stable than one with a SNR of 10dB. If you are, however on a 4Mbit plan and syncing at 4Mbit with under 6dB SNR, there's a good chance you may need to consider downgrading to a slower plan if TM techs are unable to fix your line.

Attainable Line Rate (AKA Synch Rate)
This is the maximum rate at which your modem can connect to the DSLAM if there was no service provisioning limiting the bandwidth. Anything over 2,000Kbps is considered good. The higher the number the better.

If your maximum attainable rate was 2Mbps, you would most likely be over 5KM from the exchange and have a line attenuation of over 50dB. In Aus, the cutoff is 1536Kbit or 60dB. This is borderline low, and as line conditions can change extremely rapidly I wouldn't consider it anywhere near good.

This post has been edited by skyther: Oct 22 2010, 12:47 AM

Hi all, may I know what is the normal ping time to local website or streamyx DNS ? I'm using 4MB package, n when i ping local website or 202.188.0.133, the ping time i get ranging from 150ms to 300ms, most of the time 200++ms. Before this i can get 30-40ms.

Is 150ms to 300ms normal ? If not, how do I complaint to TM ? Will they entertain problem with high ping ?

Thanks !

Are you connected to your router wirelessly? Try ethernet.

You need to perform a traceroute to see where the ping actually spikes.

ermm..my line is very bad. <40kbps download and frequent random disconnection. i think i need a central splitter from the telephone pole outside cause few months ago after i ask the technician come and pull one more line from the pole into my house,2 lines-same number.(1 line for house phone, 1 more for internet) the problem started. i already paid about Rm150 for him that time. if this time i call 100 and ask them to come, still need pay ar?

here is my statistics: 1MBps package.

Downstream Upstream
SNR Margin (dB): 6.1 11.0
Attenuation (dB): 63.5 31.5
Output Power (dBm): 12.3 16.3
Attainable Rate (Kbps): 512 800
Rate (Kbps): 416 512
K (number of bytes in DMT frame): 14 17
R (number of check bytes in RS code word): 16 16
S (RS code word size in DMT frame): 8 8
D (interleaver depth): 2 2
Delay (msec): 4 4




This post has been edited by hako: Oct 24 2010, 07:09 PM

Try disconnecting your phone, then plugging your modem into the socket where the phone previously was. Do you have a splitter going to the phone? If you do there is no need for a central splitter.

The stats on your line look pretty bad though, could be just distance.

This post has been edited by skyther: Oct 25 2010, 01:33 AM

ok the thing here is, my house no got 2 hole to put telephone line, one downstairs one upstairs. the one upstairs is direct from the pole outside, and this hole i direct connect to my modem.

the one downstairs for house phone. no splitter.

Thanks for the reply. I tried both ethernet n wireless, both giving me the same result.

N i did the tracert test, but no matter my line ok or not, I will get request timed out for all the hops except the modem.

You have 2 sockets, 1 line. The phone downstairs needs a splitter.

Which site did you tracert? What are the pings to your modem? Have you got a firewall on?

It's possible that TM's routing servers don't respond to pings. Try pinging the TMNet website and see what they are.

This post has been edited by skyther: Oct 27 2010, 03:57 AM

which kind of splitter? i try using the splitter that come together with the modem and still no change. and oh, when my phone rings or somebody pick up the phone my line disconnect.

I did tracert to 202.188.0.133, www.lowyat.net n www.tm.net.my. Ping to my modem can get 1 to 3ms ping time. N my firewall never on.

I'm not sure abt TM's routing server, but when i tried to pinf www.tm.net.my, i can get reply with 30-40ms ping time when line is normal, 200-300ms when line is bad.

Modem Status

Connection Status Connected
Us Rate (Kbps) 192
Ds Rate (Kbps) 2048
US Margin 6
DS Margin 31
Trained Modulation ADSL_G.dmt
LOS Errors 0
DS Line Attenuation 7
US Line Attenuation 3
Peak Cell Rate 452 cells per sec
CRC Rx Fast 0
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 2
Path Mode Interleaved


DSL Statistics
Near End F4 Loop Back Count 0
Near End F5 Loop Back Count 0


Router: Aztech DSL605EW


Is my line good or bad?

I noticed that streamyx throttle the upload speed at 192kbit/s

mine is
Downstream Upstream
Line Coding(Trellis): On On
SNR Margin (0.1 dB): 310 314
Attenuation (0.1 dB): 85 17
Output Power (0.1 dBm): 108 121
Attainable Rate (Kbps): 25954 1350

consider good? currently using 4mb...

I'm using Aztech 605E and a Wireless DIR300 Router
How do I check it from my wirless router?

Using 4Mb but now the data rate was only 2048 kbps previously 5120 kbps.TM Technician said outside line have to be change.It it true?Speedometer test got around 1200 mbps.Any helps. tq

Downstream Upstream

SNR Margin: 19.9 31.3 db

Line Attenuation: 44.5 24.5 db

Data Rate: 2048 509 kbps

How do I check,is there a step by step guideline,like where I go to at first? Control Panel > ??.I'm not a computer savvy person.

Modem Status
Connection Status Connected
Us Rate (Kbps) 507
Ds Rate (Kbps) 1653
US Margin 17
DS Margin 5
Trained Modulation ADSL_2plus_AnxM
LOS Errors 0
DS Line Attenuation 59
US Line Attenuation 31
Peak Cell Rate 1195 cells per sec
CRC Rx Fast 93
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Interleaved

DSL Statistics
Near End F4 Loop Back Count 0
Near End F5 Loop Back Count 0

After 12AM then Stable

this is what i got from my TPLINK TD-W8901G


i wonder is the power output is normal, coz few days ago the streamyx moron give me a new port, after that i keep getting random ADSL blinking, and when i check my phone cable it is burned and the copper wires became black colour, i wonder if it is caused by the high power from the phone line or something else

Modem Status
Modem Status
Connection Status Connected
Us Rate (Kbps) 507
Ds Rate (Kbps) 2045
US Margin 19
DS Margin 11
Trained Modulation ADSL_2plus_AnxM
LOS Errors 0
DS Line Attenuation 59
US Line Attenuation 31
Peak Cell Rate 1195 cells per sec
CRC Rx Fast 16
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path

DSL Statistics
Near End F4 Loop Back Count 0
Near End F5 Loop Back Count 0

Hi Guys,

I read the entire thread and I think I am the only one with

Data rate(Kbps) 2048 512
Noise Margin 33 17
Output power(dBm) 7 4
Attenuation(dB) 121 8

If I use splitter, the Atten will drop to 119 (a bit weird rite?) direct connection hv higher atten.

However, I do not get disconnected and sometimes up to 600+ hours (so far the longest I can remember). I do not face speed issue as my download - constantly 1.5mbps (speedtest.net) and even if I test server on Norway, its 1.3+ mbps.

So.. my problem is the very high attenuation is bothering me although I have no issues with the streamyx. Anyone can share opinion?

Thanks

Statistics -- ADSL

Mode: ADSL2
Line Coding: Trellis On
Status: Connected
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 30.6 31.6
Attenuation (dB): 5.5 7.8
Output Power (dBm): 12.3 -4.3
Attainable Rate (Kbps): 12932 1333
Rate (Kbps): 2047 511
MSGc (number of bytes in overhead channel message): 65 11
B (number of bytes in Mux Data Frame): 54 14
M (number of Mux Data Frames in FEC Data Frame): 1 1
T (Mux Data Frames over sync bytes): 1 4
R (number of check bytes in FEC Data Frame): 0 0
S (ratio of FEC over PMD Data Frame length): 0.9129 1.0000
L (number of bits in PMD Data Frame): 482 120
D (interleaver depth): 1 1
Delay (msec): 0 0

Super Frames: 105850 100889
Super Frame Errors: 0 0
RS Words: 0 0
RS Correctable Errors: 0 0
RS Uncorrectable Errors: 0 N/A

HEC Errors: 0 0
OCD Errors: 0 0
LCD Errors: 0 0
Total Cells: 8284185 2181651819
Data Cells: 181838 456751806
Bit Errors: 0 16547

Total ES: 0 712422
Total SES: 0 712405
Total UAS: 16 712399

__________________________________________________________________________________________________________________________

I also dont know this is good or not
DB108-WL crap modem