Darren, (and lml... I just read your post, and this fits what you were asking for, too...)
Thanks for that snippet from Cable Data Comm News. The first sentence of which
immediately elicited a thought or two from me.
"Cable operators have long believed success in the high-speed data business
would require that cable modems be interoperable, low-cost and sold at retail
like telephone modems and data network interface cards.".
That's quite an aspiration. At the same time, I think that it is one which is probably
self-defeating in many ways. The primary area being in extensibility of its architecture.
And to avoid any confusion about what I'm saying here, my intent is to show that this
model, in its current form, and governed by coaxial end point and head end design
parameters, will not scale to future subscriber needs.
First, a word about the opening sentence. It almost sounds like they would like to
reach a level of interchangability which is, and has been, enjoyed by the much maligned
subscriber telephone instrument. The one that hasn't changed materially, since the last century... save for some lights and a musical pad. But even these enhancements were compatible with the underlying system that supported the rotaries and the stems.
End point dumbness is not fashionable these days, but in this regard it has served well
for over a hundred years. It's time to move on in certain ways, where end points that
are far more intelligent may be more desirable (sometimes), but I needed to make this
point for contrast, nonetheless.
What will happen to the DOCSIS modem investment when MSO's pull fiber closer to,
or into, the home?
This, of course, wont happen very soon, nor will it be something that can be done very
readily for secondary reasons. Not due to the primary inhibitors which exist today. Today's primary reasons stem from homes passed cost issues. Namely higher per home passed costs of fiber labor and materials, and the lack of a suitable premises and head end set of interface standards, etc. Rather, future inhibitions will be due to some other and very old and familiar built in blockers.
These issues will come to a head at some point a couple of years out, if cable uptake
reaches that paradoxical point when its success becomes its primary cause for concern, when it can no longer handle the load it's subscribers generate. Probably when the MSOs' backs are flat against the wall in a couple of years, and users find themselves back to 56k and ISDN levels of loop performance, or in some instances, even worse.
If they stay with a shared approach, the need for native fiber or one of its derivatives
will have been reached at that point, because it will be seen as a more economically
feasible means of upgrading than the diminishing levels of return that could be achieved
from additional resegmenting.
How far can the strategy of resegmenting be stretched? Until the fifth field
reupgrade/resegment exercise, when there is by then a limitation of no more than a
dozen subscribers (surfers only, please, no so/ho's or telecommuters need apply, and
we're going to monitor that streaming stuff, so watch it!) allocated to each segment?
I don't buy the idea that QoS tiering will save the day for the cable modem regime by
that point in time. QoS may have the effect of fingering the dike, or as a band aid for
some interim period, but not as an end state solution. One reason being that the MSOs
will quickly begin to lose pops served, if they begin creating venues of haves and have
nots.
Consider what decisions the operators are left to choose from at that point. Due to the
heavy investments already made in coaxial-based modems and their CMTS's (head
ends) counterparts, the use of fiber will be further prohibited in yet another example of
how we become eternally attached to legacy systems and approaches, due to issues
surrounding the embeddedness of future extant infrastructures.
I've read, even posted about, T's strategy here in the past. Sounds good in principle, but several years into the future before making a dent wont cut it. Not when DSL's and wireless solutions are prepared to sit down to a cable lunch in two. Comments welcome.
Regards, Frank Coluccio |
