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What do the numbers in my modem statistics mean and are my stats good?
A: Most modems and routers have the ability to monitor line statistics. Some modems have very detailed monitoring while others may only show basic information.

Although what is monitored and the exact name may be different depending on manufacturer, the overall information is the same. Below are some of the common terms and measurements used to judge line quality. Remember these are not hard numbers but simply a generalization of line statistics:

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.

Used Line Rate
Your Used ATM Rate (actual service rate) plus bandwidth to cover the overhead and provisioning of the service.

DSL Rate
Your provisioned ATM Rate (actual service rate) plus bandwidth to cover the overhead and provisioning of the service.

Relative Capacity (AKA Line Capacity)
Percentage of your overall available bandwidth used to obtain your service ATM rate. For example; if your max line synch rate was 5888Kbps and you were provisioned on a 1472Kbps service you would be using 25% capacity. 1472/5888=25% capacity. The lower the relative capacity the better, but you can still get maximum speeds (although a less stable connection) even with a very high relative capacity. In other words you could be synching at 1472Kbps with 98% relative capacity and achieve maximum speeds, but you may experience more disconnects.

SN Margin (AKA Signal to Noise Margin or Signal to Noise Ratio)
Relative strength of the DSL signal to Noise ratio. 6dB is the lowest dB manufactures specify for modem to be able to synch. In some instances interleaving* can help raise the noise margin to an acceptable level. The higher the number the better for this measurement.
> 6dB or below is bad and will experience no synch or intermittent synch problems
> 7dB-10dB is fair but does not leave much room for variances in conditions
> 11dB-20dB is good with no synch problems
> 20dB-28dB is excellent
> 29dB or above is outstanding

Line Attenuation
Measure of how much the signal has degraded between the DSLAM and the modem. Maximum signal loss recommendation is usually about 60dB. The lower the dB the better for this measurement.
> 20dB and below is outstanding
> 20dB-30dB is excellent
> 30dB-40dB is very good
> 40dB-50dB is good
> 50dB-60dB is poor and may experience connectivity issues
> 60dB or above is bad and will experience connectivity issues

Output or TX Power
How much power modem (upstream) or DSLAM (downstream) is using. Maximum recommended is about 15dB. The lower the power the better for this measurement.

CRC Errors (Cyclic Redundancy Check)
CRC is a method of detecting errors in data transmission. A high CRC count in inself is not really cause for alarm. However, any increase in CRCs after your initial connection is established is a problem and usually points to a physical issue somewhere.

* Interleaving
Interleaving is an error correction protocol that is implemented for your line at the DSLAM. With Interleaving enabled, the DSLAM can correct errors in the data stream it receives before passing that data to your gateway router. It is usually implemented on noisy or marginal lines and can greatly increase sync stability and effectively eliminate "first hop" packet loss. The largest drawback to Interleaving is that it will significantly increase your ping time, specifically to your first hop gateway router.

If Interleaving is not enabled on your line, it is configured as FastPath. FastPath allows the DSLAM to pass the data received from you to the first hop router without performing any error correction. As a result, marginal lines could experience an increase in packet loss and decrease in sync stability (i.e. frequent sync loss). However, FastPath does produce decreased ping times, especially to the first hop router.

Get rid of Streamyx intermittent connection/ Unstable DSL light/ Frequent disconnection

Solve Streamyx disconnection issue in shortest time with this guide!

Check your SNR(Signal to Noise Ratio) margin and line attenuation if you are facing problems above .
SNR is a measure of the level of noise that can be tolerated before signal or data loss; SNR Margin is the difference between the actual SNR and the SNR required. It shows you the strength and stability of your connection, the higher dB the better connection stability.
Line attenuation shows you how much the signal degraded between the connection, the lower dB the better the connection. The longer distance you are from the local exchange, the higher the line attenuation.

For SNR Margin:
<= 6dB
- bad connection/frequent disconnections(Disconnected in 1-5 minutes) or can't connect at all
7dB - 10dB
-Consider average connection but still have disconnection issue
11dB - 20dB
-Good connection with no connectivity problem
21dB - 28dB
-Excellent line quality
>= 29dB
-Fantastic!

For Line attenuation:
> 60dB
-Bad Line Quality
50dB - 60dB
-Acceptable
40dB - 50dB
-Good
30dB - 39dB
-Great
20dB - 29dB
-Excellent
<20db
-Fantastic!

Simple guide to view SNR Margin and line attenuation

Go to 192.168.1.1 (common address for most of the modem) with any browser and log in with your modem username and password (Refer to the modem manual for username and password)

Kasda or ZTE modem:
WAN-> DSL-> DSL param-> Local/Remote SNR Margin & Local/Remote Line Atten.

D-Link modem:
Status-> ADSL -> SNR Margin & Line Attenuation Downstream /Upstream

Aztech modem:
Status-> Modem Status-> DS Margin & US Margin


What to do if having low SNR margin and high line attenuation?
-Try to bypass splitter and any line extension, direct connect from modem to phone socket
(although most of the chance it doesn't help! just bypass it and have a look)
-Disconnect lightning surge protector(because it will reduce the signal strength)
-Disable alarm system(if any) in house, it said to reduce the signal strength in some case.
-Call TM and they will send you technician, when the technician come, 'remind' them to:

1. Check the local exchange or DSLAM
2. Check the black cable that connect from telephone pole to your house, the cable may too old(exposed to sunlight & water) and needed to change
3. Check the wiring at the "black clip" that connected to the black cable from telephone pole (the copper wire that exposed may oxidized, reconnect the copper wire). It's the connection between your house and the pole.
4. Check the telephone pole (connection of black cable that connected to your house and the plugs up there)
All steps above should free of charge.
You can do step 3 by yourself if you want to, have to climb up to the roof.
Check also internal wiring in your house, and make sure every wire connection point you have is in good condition. Oxidized copper wire may cause to poor line connection.
If all are fine, then the house internal wiring may be too old and the line quality is bad.
Rewiring with fresh new line solve the problem most of the time.
But rewiring is not free of charge, only do it at last resort.


If your line was capped at a high speed, it will decreases the SNR margin, the SNR margin decreases as the line speed increases because the required SNR increases.
For example, if increasing the speed from 512Kbps to 2MBps raises the required SNR from 20db to 30dB then the margin left will decreases from 25dB to 15dB (assumed the actual line SNR margin is 45dB then 45dB-30dB = 15dB.)
If your subscribed package doesn't use that much of bandwidth, you can call TM to downgrade the line speed. Example, you are subscribed to 512K download and you are capped at 2M or higher download rate(Speed will still at 512K even you are capped at higher speed, the higher speed may be is for future upgrade purposes). Most of 512K users are capped at 1M for now. You can find your line speed on the same page you view SNR margin and line attenuation, different modem has different name for it, e.g. Downstream/Upstream Data Rate, US/DS Rate, Up /Down speed.

If you have disconnection problem or cannot fully utilize Streamyx, ask rebate for the difficulties period you faced by sending your request to custcare@tm.net.my, attention to billing department.

I am writing this guide because I faced the problem before and too much of frustration and disappointment at that period. Hope this guide will help and save your energy and time.
I experienced unstable ADSL light since activation. My downstream and upstream was single digit. Downstream range was 0-6dB and upstream was 0-8dB, line attenuation for downstream and upstream was 60dB-63dB. I can't connect at all at that time, sometimes I can get connected but I can't surf anything because the ADSL light started to blink after a few second. Then I called TM, the technician came and done some regular checking, after that they climbed up the roof of my house, I think they did something to the wiring at the black clip that connect the black cable from the telephone pole. Then my upstream greatly improved to 19dB-21dB, but downstream still very low around 0-9dB. The ADSL light still blinking(blinking-> stable for 10 seconds-> blinking again-> process repeated), although sometimes it became stable and can get connected, it will started to blink again in time not more than 1 hour. The strange thing was after midnight, around 1am -4am, the ADSL light became very stable and the downstream was 7-9dB, I can get connected with no problem at that time. At daylight time, the ADSL light will keep blinking and only stable for a short period(less than 1 hour) at uncertain time. I only can connect when the light became stable, have to wait for stable light(took 1 or 2 hours, sometimes 3 or 4 hours or even longer time), really wasted a lot of time. It just like depends on the "mood" of the line in order to get connected. So, I continue to call TM to report the problem, in between I had checked all the wiring and tried to solve the problem with all kind of solutions that I able to do, but the problem still remain. The technician already came many times and done a lot of repeated checking, in the end the technician climbed up the telephone pole and did something to the wiring and plugs up there, finally my ADSL light can stable for all the time and no more disconnection problem. My downstream jumped to maximum 21dB, and the range is from 12dB-21dB. But the line attenuation still the same values(distance factor, not much can be done), 60dB-63dB.
Guess how long they took to fix the problem? 2 and a half months!