Is The Router Connected?

[joka]

i haven't been able to use the adsl for a few days now, the router just won't connect. but when i turn the computer off, and wait a minute or two, the connected light comes on and stays on. when i turn the computer on again, about 15 seconds or more into the boot cycle, the light turns out again. is this normal?

i am using tot adsl with a xavi8124 router.

[monty]

Joka,

are you talking about the WAN light??

[astral]

Connect to the router via your browser,

and check the log. This will tell you what is happening.

It sounds to me as though you line is not fully enabled to the servers

in Bangkok. So the light comes on whilst the router is "trying to connect"

and goes off a few monutes later, when it gives up.

[joka]

yes, it is the wan light. i have finally connected tonight. but the bandwidth seems to be coming through in blocks, and websites freeeze when trying to access them, have to hit stop and refresh a few times. downloads are the same. it took several pause and resumes to download microsoft reader.usually the wan light is just blinking away, until it finally connects and then stays lit. can't check the router logs because it only keeps logs when the computer is on. it also won't set to the right time or day.

[monty]

Joka,

I recall you being pretty far away from the exchange!

The wan light blinking means your router is trying to negotiate a connection with the dslam at the telephone exchange...

If you lose the connection often, means either your attenuation is to high (to much signal loss due to distance), or the signal to noise ratio is not high enough (meaning the line picks up a lot of noise on the way, which masks the actual signal to much)

You can find these values in the xavi router by first going to the WAN page and then clicking on the "dsl parameters" button.

If you could post these values we wold know a lot more already.( both the local and remote values)

[joka]

Counters Local Remote

Intrlvd Fast Intrlvd Fast

FEC: 425827 0 118 0

CRC: 2219 0 0 0

NCD: 0 0 0 0

OCD: 195 0 - -

HEC: 1602 0 1 0

SEF: 0 0

LOS: 0 1

Failures Local Remote

NCD: 0 1

SEF: 0 5

LOS: 0 6

LCD: 26757 1

ok, here are the numbers on the dsl screen, hope these are the right ones, don't have a clue what any of it means.

[monty]

Not sure where you got this screen...

Not really what I talked about...

On this screen you have to choose " dsl parameters"

[monty]

And this should give you following result...

[monty]

It's the local/remote attenuation which will give you an indication about signal loss (due to distance)

And the "local/remote snr" which will tell you if the line just picks up to much noise over the length...

[monty]

Just to give an indication...

Local atten. should be under 65 db

Local snr margin should be over 12db....

[joka]

DSL Parameters and Status

Vendor ID: 00B5GSPN

Revision Number: Y1.16.3

Serial Number: xxxxxxxxxxxxxx

Local Tx Power: 11.95 dB

Remote Tx Power: 13.57 dB

Local Line Atten.: 63.5 dB

Remote Line Atten.: 31.5 dB

Local SNR Margin: 9.0 dB

Remote SNR Margin: 19.0 dB

Self Test: Passed

DSL Standard: G.dmt

Trellis Coding: Enable

Framing Structure: Framing-3

Config Data Up Down

Intrlvd Fast Intrlvd Fast

AS0(kbps): - - 480 0

AS1(kbps): - - 0 0

LS0(kbps): 256 0 - -

LS1(kbps): 0 0 - -

RValue: 16 0 16 0

SValue: 16 8

DValue: 4 8

Edited June 28, 2005 by joka

[monty]

Your attenuation of 63.5 db should not be a problem, British Telecom will try to connect customers with attenuations of up to 75db (although without guarantees).

But it seems your line is picking up to much noise! 9db snr is very low.

Should be over 12db...THis is a major problem in Thailand, with the wires all bunched together in the electricity poles

Probably why your modem only connected at 480kbs instead of 512kbps.

My guess is that your frequent disconnects are caused when the wind is rustling the wires, and temporary causing them to pick up even more noise. Since you don't have any margin as your snr is already very low, this would cause your modem to lose the connection, and will try to handshake again with the dslam (causing the wan light to blink)

The only thing you might be able to do is take care the cabling in your house is as perfect as possible. Try with a new wire from the junction box outside to your modem, keep the wire away from powerlines, and don't connect a splitter and telephone to the line...

This might give you a bit better snr, and hopefully the margin needed to avoid these annoying disconnects...

You also might want to ask TT&T to set their dslam to only allow your line to connect at max 256kbps. An adsl modem connected at a lower speed will always have a better snr ratio (as it has spare bandwidth), and hence more margin in the connection...

Not sure if they will understand your logic though

In Europe the providers will first test your line (if you are further away then 3km from the exchange) and then decide what speed they will allow you. This saves them from customers calling their support team every time someone loses connection!

I'm amazed though they hooked you up in the first place. My new house is 6 km from the exchange, and I had to beg for them to connect me! They said they do not want to connect anybody further away then 3 km! This would be overkill, even in Thailand, and especially considering the low speeds here.

[LivinLOS]

I live close enough to the excahnge but had bad lines.. Recenly changed about 150m of last leg cabling (underground.. headache) and now my line is stable and as zippy as I expect on a cheap package..

Get the local engineer to step back along your line to the junction box, its not uncommon to find lose / poor connections at various junction boxes and corroded / black copper wires..