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T1, DSL play the numbers game

T1 as a digital subscriber line replacement? For those familiar with business-class DSL services this may seem like a one-step-forward, two-steps-back philosophy. But its happening.

Even though DSL was promoted as a replacement service that was cheaper and more efficient than leasing a T1 line that moves traffic at 1.5 megabits per second, the technological and political problems swarming around DSL have reversed the situation.

Incumbent local exchange carriers are beginning to offer T1 loops at lower prices. And small- to midsize businesses dont mind paying a little extra if it means reliability and an installation time of a week or two, as opposed to the one or two months it takes to get DSL service.

Third-generation DSL access and customer premise equipment are now leaving the factory with T1 ports installed, anticipating this market shift. In fact, the demand is so high that service providers are making it a must-have service if theyre going to purchase equipment from one vendor or another.

"It comes down to Can I hook the customer up? " says Ken Kriz, worldwide product marketing manager at Paradyne, a DSL equipment provider. "Sometimes it comes down to only one way to get that customer, and as a service provider you want to have that ability."

Since before most people knew what the Internet was, T1 was the traditional means of providing businesses with high-speed data access. Its a dedicated leased line provided by the regional Bell and resold by service providers. Since its a dedicated line that is highly reliable and takes up more resources than one copper phone line, T1 access is more expensive, previously sold at monthly fees of up to $1,500.

When DSL entered the market, it was seen as a T1 replacement, theoretically providing 2 Mbps to 3 Mbps transmission rates at about $80 per month. But if it sounds too good to be true, it usually is. DSL has had problems with reliability and, when it goes down, service providers havent been quick enough to bring it back up to avoid leaving consumers with a bad taste in their mouths.

Also, DSL isnt available to everyone in a serving area. DSL is limited in the distance it can be deployed from the local carriers central office, usually between 12,000 feet and 18,000 feet. Erin Dunne, director of research at Vertical Systems Group, estimates about 40 percent of potential business customers are beyond these distance limits. "However," Dunne says, "virtually all of these customers can be reached by T1 lines."

Many businesses are in areas that are served by digital loop carriers, large remote terminals installed to extend the reach of the central office. The only form of DSL that passes through these DLCs is IDSL (Integrated Services Digital Network DSL), the slowest form of DSL at 144 kilobits per second, yet one of the more expensive, running as high as $110 per month. However, T1 can go just about anywhere.

"When you get to a DLC, your only choices are IDSL or T1," explains Matt Byrd, a spokesman at DSL equipment maker Net to Net Technologies. "Well, if youre a customer that wants something more than 144 Kbps, then you either have to bond multiple IDSL lines, which can get really expensive, or use T1."

And Byrd explains that, in terms of distance, "T1 can go from here to the moon," because the signal is repeatable.

But none of this matters if T1 costs $1,500 per month. Byrd says it doesnt. In fact, T1 access can cost from $50 to $1,000 per month, depending on the region, and thats why the technology has turned into a replacement access loop, when service providers cannot reach their customers with DSL.

"We on the equipment side need to offer T1 as part of the whole DSL package," says John Nevius, product line manager at Copper Mountain Networks, which recently announced T1 line cards for its DSL access equipment. But its not difficult for the service provider to add T1 services because they "just need to slide in a new line card and update the equipment software."

Competitive local exchange carriers Mpower Communications and Network Telephone have already begun offering Copper Mountains solution, so far with good reviews.