History has a way of “repeating” itself …
July 8, 2008
So much material out there, so little time to knock some commonsense and reality into the mix.
Last night at home, while reading a few technical articles on bend sensitive single mode fiber various points were made about the applicability to Passive Optical Network or PON fiber based distribution architectures. Outside of I need to get a life after work, I am amazed how simple solutions are available but we complicate the living hell out of things.
There is no basic argument that GPON and GEPON are capable of delivering Giagabits (that’s Gigabit with an “s”) synchronously. Moreover, the need for racks, power and structured cabling goes down by factors while reliability in comparison to copper, or fiber/coax increases by factors. Sparing you the drudgery of the technical arguments, a core thesis of how to implement, measure and maintain different service level agreements over a PON path became a sticking point. (Did I forget to say copper access is not a long term business model).
In my reading, this SLA management question within PON’s developed into a whole new generations of chips that the authors believe would need to be developed to manage SLA’s over a 10 gig PON, 40 gig PON, 100 gig PON… you get the picture. The problem that is being wrestled with is managing “light” spectrum based upon SLA’s.
The problem I had with designing new chips, is the parochial view that the problem belies the that the SLA quandary limitation exists based upon a single fiber or fiber pair for multiple SLA’s.
Well, here is my news flash. What is stopping anyone from dedicating fiber pairs to different SLA needs today as opposed to waiting for the “god” chip for a single fiber strand or fiber pair. Actually nothing … unless you don’t own any local fiber or can’t get access to any local fiber. Who can afford to wait?
This same logic applied to the great long haul land grab of the 1990’s which drove DWDM boxes through the roof. DWDM was designed for long haul since you have very little add/drop splice points in a long haul network thus distance and efficiency counted for those that could only garner a fiber IRU or fiber lease. But as the long distance industry contracted (collapsed) the DWDM companies decided to sell DWDM as a solution looking for a problem and since long distance was dead, they took the square box and sold it to fit in the metropolitan network hole in search of fixing something that alternatives were readily available. DWDM gets real expensive in metropolitam deployments, the laser tolerances are extremely tight, signal regeneration costly, and the loss budgets excell due to the magnitude of splicing that occurs as one goes from long haul to metropolitan backbone and finally last mile access. Typically the question is how many PhD’s per mile does it take to maintain DWDM tolerances in the metro?
What’s my point, multiple fiber pairs gives you multiple options, flexibility and opportunity to differentatite. Banking on tightly spaced nano-window lasers, expensive repeaters and db loss tolerance of dispersion, can be more costly that what multiple fiber pair alternatives provide.
I get a kick out carriers that overbuilt certain routes in a market by “joint building” with other carriers on the same route when the use DWDM. Here they have gobs of fiber power and they take the most expensive way to light it. Now, it wasn’t to smart to have joint built, but some bean counter in the telecom bubble days probably thought they were “saving” money.
Bottom line … do your homework. Don’t wait for the next chip … get innovative. When someone is trying to sell you a NASA solution when you can do quite well with an abacus … take the time to look at real demand and technology evolution.
The next god box or god chip is always touted on our telecom media websites or magazines… like we are missing out on something …
We have waited over 25 years for convergence to become quasi reality … what more do we need to know about the real rate of technical, ubiquitous change … it is slow in coming.
Focus on staying in business first, the rest will follow.
And remember: the softest pillow is a clear conscience.
Written by Dave Rusin - Telecom ExecutiveComments
2 Responses to “History has a way of “repeating” itself …”
Got something to say?











Nice
Funny line about the PH’D’s….I spent years asking the ’smart people’ why they wanted to cram two pounds of baloney on a fiber when they have 863 spares under the sheath…but what does an OPS guy know anyway?