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Dry lines (alarm loops) in Canada

We currently use business DSL. We want to hopefully improve our network reliability by having some semblance of control of what goes at at the ISP at the other end of the connection (for physical line redundancy or service monitoring). We thought one way of doing this is doing SDSL point to point to the ISP using a leased line as described in this article:

Are dry lines inexpensive to order from a Telco? Are there any home and pop ISPs in Canada (specifically Toronto, Ottawa, Montreal and Vancouver) who do offers to provide uplinks provided you buy a pair of SDSL modem and lease a dry line (alarm loop) from your house to their office? What sort of speed is legal? What should I pay? Are there any more modern alternatives? Are the canadian CRTC against this? What are the loop-holes or taboos I should be aware of? We are telco experts so please break it down for us! Much much thank for any inputs!

Dreaming of cheaper uplinks
Tuesday, September 30, 2003

Sorry, I meant we are not telco experts!

Dreaming of cheaper uplinks
Tuesday, September 30, 2003

What I can't understand, is why don't you ask your local telco?

Jack "Destruction" Ken
Tuesday, September 30, 2003

I'm certainly no telecom expert either, but here's what I have gathered from online discussions. Basically, the phone companies are aware of the dry copper pair "dodge" for DSL like speeds and they will either require proof that you intend to use the pair for an actual alarm circuit, or they will outright refuse. 

The technical problem seems to be crosstalk (AKA interference induced by EM fields) between the copper alarm circuit used for high speed data and the voice circuits that share the same physical conduit. DSL data speeds are on the order of megabytes, and digital data is basically square wave in nature which in turn is VERY rich in harmonics...  And, you have to have the phone company remove all inductance causing components between you and the uplink in order to support these speeds.

I think that basically, the phone companies consider use of an alarm circuit for high speed data as a misuse.

However, I haven't talked to the phone company myself. Maybe it's not as bad as I have been lead to believe. It would be REALLY interesting to hear what you find.

Bored Bystander
Tuesday, September 30, 2003

Really depends on where you live in Canada. I live in Waterloo Ontario. You can get SDSL, there are even providers who want to sell it to you. The problem we had was that we were growing and moving offices so fast (4 times last in last 2 years) that having an "HARD" line was bad news since its cannot be moved, you will have to incurr the capital costs of laying another one when you move. We just sucked up the DSL and Bell just dinged us for the installs when we moved (about $450 each time  if I recal correctly).

if you need more than the full rate DSL, I suggest getting a 2-4U server and go co location in a good data center thats right on some sort of OC line. if you want to telecomute into the office i suggesting getting a NAT/VPN and getting one of the residential high speed services like sympatico or rogers high speed.

Michael Johnson
Tuesday, September 30, 2003

Hey thanks!

Dreaming of cheaper uplinks
Wednesday, October 1, 2003

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