Mike:
As I understand it HDSL2's big advantage over HDL is is needs only one wire pair,
instead of two, and it can go 12 Kft in distance. This is suitable for most business and
small offices, which tend to be close to COs, and it is really good for PBX or leased lines
to businesses; you can double your access rate by going from HDSL to HDLS2 without
laying any fiber or copper, or buying new internal equipment.
I think technical people tend to overestimate the replacement rate of transmission media.
The real history of telecommunications can be categorized, in one view, as the history of
making more out of the same. Thus some people are surprised to see 'legacy' systems
such as SONET and ATM (developed in the 80's) still around and not yet replaced by IP
(developed in the 60's). People who make claims often don't have much real life
experience, particularly in management of networks
You might say, they haven't a legacy to stand on.
Sorry for the pun.
What will kill this business is:
1) either small business all decide they need more than two t1's access,
2) fiber comes down so low it is cheaper to run it to a building than to replace t1
equipment with HDLS
I haven't checked the marketing forecasts, but I think 1) is unlikely. If I need a lot of
bandwidth, I would go right to fiber, but if I'm building a small company, I'll stick to
sub-t1 access, particularly if it resues copper.
Now 2) may happen. There may be cases where a large building may distribute lines
internally and need a fiber or something to handle the accumulated access of many small
companies (like a mall?) Also, I've personally heard of a case where a candy company,
with very limited voice and very very limited data needs was offered a fiber by a CLEC.
It turned out that pulling the fiber was the responsibility of the local ILEC, and they had to
subsidize it for some reason I still don't understand.
Thus 2) seems to be the critical issue. I've seen posts before giving cost information on
fiber, but only vs. running NEW copper: it may be at parity today- some claim it is
cheaper to run fiber. But I suspect that most small businesses don't need more than a
single T1 (one pair HDSL2), and if they do grow, they don't need more than 2 T1s (two
pairs of HDSL). At that point the question is will their growth be satisfied by two pairs or
do you force a move to fiber, or is three pairs still a better option.
I've said it before and I'll say it again- the only application I see needing high bandwidth is
point to point video- that might require a tripling of 'voice' capacity. At that point fiber
may be needed.
I say five years as a guess. |
