Replacing home DSL with mobile internet ?

[Varn]

I normally look at the web at home on my cell phone modem. As far as performance goes it is borderline pathetic. Still better than the 3kbs that my home phone had 3 years ago.

Not everyone lives near a state capitol or major city. I have two main locations that I access the internet at on my cell phone modem. One is in Missouri and it usually gets 160-300kbs I have another location in Illinois that I am lucky to get 160kbs. Neither location is line of sight.

The place that gives me the best signal is in the woods. The place that gives me the worst signal is at the highest point in the county and is about the same distance to a tower. I can barely view a you tube video.It is full of starts and stops when everything is perfect.

Nothing happens in my world at a million characters per second. Of course the best thing about my location is the lack of people. No traffic lights, lack of civilization. No one around me has anything funny on their vehicles.

[PhilA]

Everything Snax said. This is then in addition:

I'm not sure what detail you'll get from ATT but there's a few things that you should be trying to find out.
If you have a login into your modem you can get most of it.

a) Distance from the node/dslam. To get a decent 1.5Mbps down I'd say less than 18,000 feet on 26AWG copper. 20,000 if you're on 24AWG (unlikely).

b) wiring routes within the house from the demarc. If your telco provider service ends at their demarcation point outside, run a dedicated pair to the modem. Avoid splitters like the plague. They corrode and get noisy. Check all connections for signs of corrosion. Wall jacks go bad for no reason, even when they look good. Older jacks lose the springiness in their pins and make for noisy connections.

c) 3-way splitters from Radio Shack and Walmart are evil and for some reason cause problems with DSL. Throw them away. They all seem to be made the same and have crosstalk problems.

d) What transmission mode is your ISP providing? G.Lite? G.DMT? ADSL2+? (Three of a possible many). At distances over 16,000' if your modem is trying to train G.DMT and be throttled you'll get abysmal throughput, even with Reach-Extended ADSL2. Some modems can work a lot better at distance by being switched onto "Interleaved" mode. This is at the ISP end, and I'm not sure how willing your ISP will be to discuss the way they make their system work for you.

e) What's your SNR and attenuation? Ideally you're looking to get the entire-line attenuation below about 31dB. in the mid-to-upper 20's is good, low 20's to about 15dB is excellent. 6dB on the SNR is about the minimum to give a solid connection, albeit slow, over 12dB will give a much better connection. Forget not that you eat into the SNR margin the greater the bandwidth is being able to be used. The better the SNR, the more bits per tone can be encoded accurately, and the faster your connection will be, and the better the error correction and recovery. See if you can find out if your HEC (Header Error Count, basically packets that arrive so mangled they can't be repaired and are discarded) climbs steadily. It should hardly move- on my line here my HEC is 1350 packets in four months of operation.

DSL can be wonderfully reliable, given good line characteristics. You just have to make allowances for the fact it's a newer technology piggybacking over a very old technology. Wireless is fickle compared, and subject to transmission problems totally out of your control. You can control the copper within your house and improve it. You can't stop your neighbor arc-welding...

Clean the line up inside the house and you should see an improvement. Also note that if your modem has been fighting poor line conditions for several years the amplifiers might not be in tip-top shape any more, having run at max amplitude for a long time.

Hope that helps.

--Phil

[dremd]

Thanks Phil.

I actually had a funny story with my DSL over WiFi (medium range) link today.
Basically, I lost signal, drove over to my remote site, and there was 2 dump trucks and a road paver parked right in front of my remote equipment. Now if only they would pave the road with traffic .

[Snax]

One thing that never ceases to amaze me is the exceptions to the rules on DSL. I've seen solid 1.5Mbps connections on loops as long as 22,000 feet, and crappy connections at the same on under 10,000 feet. Even when all available techniques for getting the most out of a circuit are employed, sometimes it simply boils down to the type of cable the signal runs through and what other circuits occupy adjoining pairs.

In that vein, it's reasonable to try to get more speed out of circuits that don't meet the rule of thumb, but often counterproductive to touch those that do. I.e., if it ain't broke, don't 'fix' it!

It's also worth noting that telcos use a mix of technologies to deliver DSL. Just because they serve one area with G.DMT, doesn't mean somebody next door isn't running on the original CAP! (Yes, there are still a few stragglers around here.) It's also worth noting that proximity to the central office isn't the end-all indicator of speed potential for non-fiber DSL. I live less than 1000' from the central office that serves me and can only get 12Mbps/896. People further out running on fiber fed remote DSLAMs by contrast can get 40M/20M! (Knowing the system, it boils down to a trunking layout issue, but that's beside the point.)

[PhilA]

Yep. We have one or two customers on 26AWG at 33,000'. That's cheating a little because we've got a line repeater in the circuit. That was pulling 2.6Mbit and 350k.
We have one or two customers at 21,000' and they have a fairly steady 1.5Mbit/512k running on reach-extended adsl2.

Over 90% of the time our DSL problems are in the last few yards of wiring.

Multi-core wire put into an auto-punchdown demarc (yeah, it has dialtone but the attenuation is so high because you're only just making contact with the wire), splitters into splitters into splitters.

The last thing we have trouble with is load coils on the lines. We've had a few that haven't shown up on the line test equipment, which is usually good down to the last few feet of wire to locate it. That really attenuates DSL. That and waterlogged crimp connections.

Like I'd said, and I think you'll agree, that's what you get when you push something over a line that was never designed for it.

That said, I'm currently running 16.5M down and 2.5M up over copper. I'm 3200' from the office.

--Phil

[Varn]

I don't completely understand the nomenclature but I understand 26g wire, distances and waterlogged connections.

My land line at home was verizon and they would not consider anything more than was already in place, I am 5.5 miles from their hub. A mile away the rural coop was running TV through their lines I could not pull more than 3kbs. My office is across the street from their switching terminal, I refuse to use their service as they are being prickly about extending their "good" coverage out from their hub.

Originally Posted by PhilA

Yep. We have one or two customers on 26AWG at 33,000'. That's cheating a little because we've got a line repeater in the circuit. That was pulling 2.6Mbit and 350k.
We have one or two customers at 21,000' and they have a fairly steady 1.5Mbit/512k running on reach-extended adsl2.

Over 90% of the time our DSL problems are in the last few yards of wiring.

Multi-core wire put into an auto-punchdown demarc (yeah, it has dialtone but the attenuation is so high because you're only just making contact with the wire), splitters into splitters into splitters.

The last thing we have trouble with is load coils on the lines. We've had a few that haven't shown up on the line test equipment, which is usually good down to the last few feet of wire to locate it. That really attenuates DSL. That and waterlogged crimp connections.

Like I'd said, and I think you'll agree, that's what you get when you push something over a line that was never designed for it.

That said, I'm currently running 16.5M down and 2.5M up over copper. I'm 3200' from the office.

--Phil