Dsl Question

[sbk]

OK, I am too far from the main station for DSL for the island but have been given it anyway (thanks!) it works during the day with no problem (ok, a bit slow but still miles better than dial up--so no complaints there). But, at night, because of the distance and the electrical interference on the line, we lose the signal.

My husband was wondering, if we signed up for a better package (ie 512 or 1024) would the signal be stronger and perhaps reach our house at night? Or is that not related to signal strength at all?

[monty]

Hi SBK,

Unfortunately not!

The higher the speed, the more difficult it is for the modem to hold the connection!

It might go faster during the day, but in the evening the modem will downshift speed trying to maintain connection, all the way down till 32kbps, and under that the connection will drop out...

You might try to borrow a different brand of modem, some are better then others on marginal lines!

Cheers,

Monty

[sbk]

OK, thought it was worth asking anyway

My husband is friends with the TT&T guys and they tried several different modems to see if one worked better than another. No luck. You don't have any idea what brands might be better on marginal lines then?

[phazey]

Do you have any friends/relatives who live a few hundred metres nearer to the DSLAM/Exchange site ?

[autonomous_unit]

There is actually a slower DSL standard that tolerates bad lines... I seem to recall it is 114 kb/s for some reason, and I had it once in the US about 5 years ago. But, I guess they do not have this available or they would have thought to try it. Did they try 128 kb/s?

[sbk]

Do you have any friends/relatives who live a few hundred metres nearer to the DSLAM/Exchange site ?

the inlaws are abit less than a km away from us, a km closer to the site, that is. What did you have in mind?

***thought I should add, there is a place with DSL that is close to my inlaws house (between us and them) and his does not cut out at night.

[girlx]

even when you are close to the signal, ADSL in Thailand is ridiculously unreliable and slow, unfortunately. mine drops out quite frequently as well and i am on the 512/256 package.

[nikster]

Do you have any friends/relatives who live a few hundred metres nearer to the DSLAM/Exchange site ?

the inlaws are abit less than a km away from us, a km closer to the site, that is. What did you have in mind?

***thought I should add, there is a place with DSL that is close to my inlaws house (between us and them) and his does not cut out at night.

If you have a line of sight or near line of sigh to in-laws you could do what I did: Install a DSL at in-laws and a wireless link from them to you. This can be very simple - but only if there's a line of sight.

Equipment you need:

- 2 Wireless Routers either Linksys WRT54G or DLink DWL-2100AP, 2700 Baht each

- 2 Directional Antennas 19dbi gain or more, 4000 Baht each

Hook up router 1 to the DSL, set router 2 to "repeater" mode, point the antennas at each other, done. If you are unsure, the shop that sells the antennas knows how to do it, they offered to do it for me for 2000 Baht. Full DSL speed.

However, if there is a hill in the way, or trees, or anything else that's more substantial, you are out of luck & it won't work. You need a direct line of sight.

Edited December 21, 2006 by nikster

[monty]

1 km is easy to do, but you need line of sight indeed.

If you have line of sight, on that distance even the cheapest directional antenna will do...

[Richard-BKK]

What helps sometimes if the DSL signal is not strong enough, you take the hook of the telephone and let it of the hook for 15 minutes. After a few minutes the line starts to make a loud peep sounds, after that the telephone signal will be death. Leaving the whole connection for the DSL signal.

Again this work sometimes if the signal is just not strong enough....

[sbk]

Can the antennae be tall? Hills aren't really a problem but it is solid coconut trees between here and there.

[sbk]

What helps sometimes if the DSL signal is not strong enough, you take the hook of the telephone and let it of the hook for 15 minutes. After a few minutes the line starts to make a loud peep sounds, after that the telephone signal will be death. Leaving the whole connection for the DSL signal.

Again this work sometimes if the signal is just not strong enough....

tried that one already

[nikster]

even when you are close to the signal, ADSL in Thailand is ridiculously unreliable and slow, unfortunately. mine drops out quite frequently as well and i am on the 512/256 package.

You might check out your line and your router. I find it pretty reliable even though I am quite far from the station (> 3.5 km) and basically online 24/7. I am on a 1024/512 package from TOT.

It's not as good as back home, there are some drawbacks:

- High pings (300 - 400ms)

- Slower downloads - stay around 60KB/sec max most of the time

- Those days where it would be down for 1 or 2 days. Happened 2x in 2006.

Other than that - working splendidly. There are weeks without any outages.

My neighbor's on the other hand goes down all the time, multiple times a day. But he has a crap phone line (lots of static) and a bad modem.

I also used to have a Billion DSL router which went down a lot - lots of hard restarts required. Now I have a Zyxel and it just works. It makes a difference...

[nikster]

Can the antennae be tall? Hills aren't really a problem but it is solid coconut trees between here and there.

Well - you can mount the antennas on tall towers of course. I know that you can get 2m or 8m shielded cable from your router to your antenna. This is important as normal cable won't do - you need to hook up the wireless router via a shielded cable to the antenna. The people who sell the antennas also sell the cables.

All in all, it really depends on your conditions over there. If there is a solid coconut forest, you will have to mount the antennas above it, if it's just a few random trees it might be strong enough to blast through. If your house is already high, has a terrace on the roof, etc, then that might be very easy.

The rule of thumb is: If you can find locations to install antennas such that they can see each other, you won't have any problems.

If they can't see each other it may or may not work but probably won't. Wireless networking is not an exact science.

Unless you really enjoy playing around with this stuff, your best course of action would be to hire the company that sells the antennas to try to make it work. They tend to want to sell you equipment that's way too large, but the advantage would be that you could make a deal with them whereby they try it, and if it works you buy all the equipment off of them, and if not you compensate them for their time and they keep the equipment. It's possible to try that without moving the DSL first.

If you don't want to spend that much and have a nephew that's into this sort of thing, it's very cheap to make home-made directional antennas, as little as $5 in parts. All you need is a can the right size (pringles can is the classic), some screws and a bit of copper. Personally, I would rather spend BHT 4000 than spend the time to do this.. but that's because I am just no good with hardware.

PS: For example, I am using this antenna right now:

http://www.trendnet.com/fr/products/TEW-AO19D.htm

Edited December 22, 2006 by nikster

[girlx]

You might check out your line and your router.

nah already checked and both are fine, according to TT&T it is a problem with their servers in surat thani- they go out every time the wind blows.

[lomatopo]

It would be interesting to know the characteristics of your line. Often there are bridges/taps in place that are no longer required and can be removed. Also you could ask your service provider about installing a remote DSLAM, between your location and the serving central office. Perhaps there are other customers who could be served and the cost could be justified. The additional 1 km, and wireless set-up might be OK but you should check the DSL performance at the home closer to the serving CO to make sure it is acceptable before commiting to that solution.

It used to be that if you matched the chip-set on the DSLAM port and the modem you would get the best possible performance, but this is less of an issue these days.

[sbk]

the line is old and crappy One part was spliced back together where a falling coconut tree cut it in two.

Getting a DSLAM exchange is unlikely. But is worth asking the guys next time they come out. Maybe if we can get a few more bungalows in the area interested in signing up for it they would consider it.

[nikster]

the line is old and crappy One part was spliced back together where a falling coconut tree cut it in two.

Getting a DSLAM exchange is unlikely. But is worth asking the guys next time they come out. Maybe if we can get a few more bungalows in the area interested in signing up for it they would consider it.

Do you actually have static on the line? You could just ask for a shiny new line - can make a big difference... even pay for having them do it... I moved my DSL line to another house. TOT actually had to put in about 1.3km of cable up on the electricity poles. There was no phone there before. They did it, and it cost me 7000 Baht. Pretty reasonable if you ask me

[nikster]

It would be interesting to know the characteristics of your line. Often there are bridges/taps in place that are no longer required and can be removed. Also you could ask your service provider about installing a remote DSLAM, between your location and the serving central office. Perhaps there are other customers who could be served and the cost could be justified. The additional 1 km, and wireless set-up might be OK but you should check the DSL performance at the home closer to the serving CO to make sure it is acceptable before commiting to that solution.

It used to be that if you matched the chip-set on the DSLAM port and the modem you would get the best possible performance, but this is less of an issue these days.

I completely agree with that. No use doing all that wireless setup unless the DSL is a lot better 1km down.

lomatopo, how would I go about testing a phone line for DSL-fitness? Are there tools on the PC? Or through the modem? My DSL modem has some options but they don't look to be very sophisticated. It shows TX/RX bytes and "errors" - I suppose thats the number of errors. I would really like to know exactly how good my line is...

[monty]

What modem you have?

Most have a bit more info on line quality, both attenuation and SNR (signal to noise ratio) are the most important..

By checking them early evening in regular intervals until the connection drops might give us a better idea of what's happening!

[sbk]

Is this what you are looking for?:

Upstream:

noise margin upstream: 31 db

output power downstream: 11 db

attenuation upstream: 31 db

Downstream:

noise margin downstream: 17 db

output power upstream: 12 db

attenuation downstream: 63 db

This is at 3:23 pm

The modem is a Zyxel ADSL 2 access router P-660r-t1

Where can I look in my modem info in order to answer your questions?

[monty]

Are you sure the upstream attenuation is correct? Normally upstream and downstream are roughly the same, as attenuation is mainly a result of the length of the line.

my numbers are:

Connection Status Connected

Upstream Rate (Kbps) 128

Downstream Rate (Kbps) 256

US Margin 31

DS Margin 17

DS Line Attenuation 60

US Line Attenuation 63

These are my numbers, roughly the same as I also am too far from the exchange (8km). Your numbers indicate that your connection should hold with no errors in the transmission.

As long as your noise margins stays above 12 db, you should be alright.

You can see clearly that the noise margin is influenced by the connection speed. Your download speed is double that of your upload, hence your noise margin on your upload is double as good as your download margin.

Try to keep a log later today, especially around the time the connection starts to get iffy...like ever 10 minutes.

If your upload noise margin is still good just before the connection pops out, you might try to convince the TT&T technicians to set the dslam at 128/128, and you might be able to keep connection all night.

[sbk]

I copy pasted from the modem, so that is what it had on it.

Would the dslam change affect everyone who uses the DSL or just me?

[monty]

Nope, just you...

Every adsl subscriber basically has a modem at the exchange's side assigned. It's where they can set the maximum speed your adsl link will connect.

Lowering the downstream to 128 kbps will bring your noise margin in the 30db range (like your upstream now), giving the modem much more resistance against line noise (the actual signal is much clearer against the line noise)

[sbk]

OK, I won't give you the full log just the last few checks because basically the numbers stayed the same for an entire hour.

5:45 pm

noise margin upstream: 28 db

output power downstream: 10 db

attenuation upstream: 31 db

noise margin downstream: 17 db

output power upstream: 11 db

attenuation downstream: 63 db

5:53 pm

noise margin upstream: 28 db

output power downstream: 10 db

attenuation upstream: 31 db

noise margin downstream: 17 db

output power upstream: 11 db

attenuation downstream: 63 db

5:56 pm

noise margin upstream: 28 db

output power downstream: 10 db

attenuation upstream: 31 db

noise margin downstream: 17 db

output power upstream: 11 db

attenuation downstream: 63 db

5:58 pm

noise margin upstream: 28 db

output power downstream: 10 db

attenuation upstream: 31 db

noise margin downstream: 17 db

output power upstream: 11 db

attenuation downstream: 63 db

noise margin upstream: 0 db

output power downstream: 0 db

attenuation upstream: 0 db

noise margin downstream: 0 db

output power upstream: 0 db

attenuation downstream: 0 db

[monty]

strange,

you go from a perfectly sustainable connection (noise margin over 12db, attenuation under 65db both on upstream and downstream) to nothing!

Looks like indeed there is a sudden appearing strong interference...

[nikster]

Are you sure the upstream attenuation is correct? Normally upstream and downstream are roughly the same, as attenuation is mainly a result of the length of the line.

my numbers are:

Connection Status Connected

Upstream Rate (Kbps) 128

Downstream Rate (Kbps) 256

US Margin 31

DS Margin 17

DS Line Attenuation 60

US Line Attenuation 63

These are my numbers, roughly the same as I also am too far from the exchange (8km). Your numbers indicate that your connection should hold with no errors in the transmission.

Wow I had no idea you could even get a signal 8km from the exchange!

Thanks for the info on noise margin and attenuation, much appreciated. I was wondering how to do that. Here's from my Zyxel Prestige 660H-61 for comparison. I am not too far from the exchange, about 3.8km, at 1024/512:

noise margin upstream: 21 db

output power downstream: 16 db

attenuation upstream: 31 db

noise margin downstream: 18 db

output power upstream: 11 db

attenuation downstream: 47 db

[mtls2005]

The donwstream attenuation number of 63 db is the problem. That means that your modem is receiving ~ one, one millionth of the power of the signal from the DSLAM in the serving CO. So you are pretty much right on the edge. However with this line characteristic a maximum of 512 kbps should be achievable? Also based on the figures provided it looks like there was a complete loss of signal, or the line degraded to the point where you lose synch. Are you using any kind of line filter (could be incorporated into the splitter)? Do you notice any degradation, or other issues, with your fixed line (noise, static, humming, buzzing, clicking)?

I'd try a filter, then maybe ask the service provider to run a full test on the line, then maybe pay for a new line to be installed or a remote DSLAM/streetside cabinet. Maybe ask if they are using any remote cabinets currently. If not then they would probably not do one for you.

[sbk]

We do have the standard filter on it. Didn't make a difference with or without.

Our main problem is a few km of streetlights that come on about 5:55 pm every evening, they are on the same poles as the phone lines and right at phone line level. I guess our signal is just not strong enough to beat the street lights.

How much would a remote cabinet run? Ie if we could get enough neighbors willing to sign up for DSL they might go for it. Just have to see how many neighbors it would take!

[aznyron]

We do have the standard filter on it. Didn't make a difference with or without.

Our main problem is a few km of streetlights that come on about 5:55 pm every evening, they are on the same poles as the phone lines and right at phone line level. I guess our signal is just not strong enough to beat the street lights.

How much would a remote cabinet run? Ie if we could get enough neighbors willing to sign up for DSL they might go for it. Just have to see how many neighbors it would take!

Now if only you tech neks could get a job with TOT or TTT and maybe we could get a decent adsl service I just dump mine I was payinf for 1gig and was just getting above 56k dial up going out side the country inside thai it was OK but I need to reach the WWW not just Thai web sites I tried satelite last year either they installed wrong because it sucked or that the way it is in Thailand I was told 2 years ago the Thailand was going to be internet savy in 2 years that means installing fibe optic lines so far I have not seen dilly ship any one out there have any advice I am all ears