High Line Attenuation the problem?

jaws104

I suffer from frequent but not random disconnects. Every night from 10ish it will start dropping and reconnecting every 10 mins or so for the rest of the night. It's fine during the day

So with little help from my ISP (UTV) I dug up the line stats during one of the up and down sessions. I read that over 50db line attenuation can cause line drops.... any advice on where to go from here? BTW I'm Blackrock Dublin, on the Dunlaoighre exch. I think


ADSL Line Type G.DMT
ADSL Line Coding INTERLEAVE

Line Attenuation (Down):52 (Up):30

Noise Margin (Down):12 (Up):13

Total Output Power (Down):20 (Up):2

Current Rate DownStr: 1792(K) UpStr: 256(K)


ADSL Line Status UP
Relative Capacity Occupation (Down):100 (Up):44

FEC(FAST) (Near):0 (Far):0
FEC(INTERL) (Near):0 (Far):0
CRC(FAST) (Near):0 (Far):0
CRC(INTERL) (Near):0 (Far):0
HEC(FAST) (Near):0 (Far):0
HEC(INTERL) (Near):0 (Far):0
Showtime last(sec) 60
ADSL_FW_Version ASW_R13_9_38
ADSL_Board_Type ANNEX_A

Hank Scorpio

prolly a mix of both

are u plugged directly into the main phone socket, try unplugging any devices within the house

lucernarian

You have a high enough attenuation, but that's only half the problem.

I've seen problems like this before, where the disconnects are after a certain time in the evening. The best theory I've heard is dodgy streetlights interfering with the DSL signal. This is likely in your case as you've a line roughly 3 miles long going nearly entirely through an urban area.

I pity you being on UTV as the poor feckers on front line support will definetely not have a clue as to the physics involved.

To confirm the theory: if you can see streetlights from your house, see if the disconnects coincide with light-up time.

jaws104

To_be_confirmed wrote: »

You have a high enough attenuation, but that's only half the problem.

I've seen problems like this before, where the disconnects are after a certain time in the evening. The best theory I've heard is dodgy streetlights interfering with the DSL signal. This is likely in your case as you've a line roughly 3 miles long going nearly entirely through an urban area.

I pity you being on UTV as the poor feckers on front line support will definetely not have a clue as to the physics involved.

To confirm the theory: if you can see streetlights from your house, see if the disconnects coincide with light-up time.

Hmm the streetlight theory is interesting but depressing at the same time. Not a hope in hell of the problem being resolved if that's the culprit.

smellslikeshoes

jaws104 wrote: »

Hmm the streetlight theory is interesting but depressing at the same time. Not a hope in hell of the problem being resolved if that's the culprit.

The street lights (if it is them) are only half your problem. You line is pretty long, you might have better reliability if you want down to 1mbit though there is a chance that won't do anything for you either.

dub45

As a matter of interest does your noise margin vary a lot? I had a dodgy enough line and I find I have the problems when the noise margin varies considerably.

There was a fairly long thread on here a while ago about the street lights theory not sure it got anywhere though!

lucernarian

If the disconnects are repetitive and regular, then the problems can be narrowed down. Have a look in the router's log and see what time they're at. If you can, note for a few evenings exactly when the problem starts to happen. We need an accurate picture to answer your question.


I can answer that question for you dub45. Seeing as the line disconnects fairly frequently at times, despite a signal margin of 12dB reported below, you can safely say the signal margin dropping towards 0 dB is a substantial variation, and frequent too if it warrants a post here on boards.

As for attenuation, if a 51dB line can't handle 2 mbits, there's usually something wrong with the line itself (not necessarily eircom's fault).