[70933] in North American Network Operators' Group
RE: Cable networks RE: best effort has economic problems, maybe OT
daemon@ATHENA.MIT.EDU (frank@dticonsulting.com)
Tue Jun 1 21:32:59 2004
Date: Tue, 1 Jun 2004 20:32:16 -0500
From: <frank@dticonsulting.com>
To: <nanog@merit.edu>, "'Christopher J. Wolff'" <chris@bblabs.com>
Reply-To: frank@dticonsulting.com
Errors-To: owner-nanog-outgoing@merit.edu
>>So what's the cable HFC Achilles heel?
As an observer, only, here.... ;)
... for one thing, investment is one of HFC's weaknesses as it relates to
alternative transmission techniques in the broadband space, as witnessed by
Rainmaker Technologies' early out. And while Narad's team may tell you that (and
here I'm now getting this part second hand) they can customize a downstream mesh
or ring for reliability and failover purposes, the reality is that most of these
will go in as linear spurs off the local neigborhood block amplifier or
thereabouts in an unprotected manner. And then there are the intrinsic capacity
constraints imposed by coaxial's distance-attenuation characteristic, facing a
ceiling far lower than that of optical fiber.
I've been impressed with some of the other MSO-related endeavors, however, where
they've implemented native fiber rings - sans coax - for GigE and SONET
applications to industrial/corporate parks and educational campuses, going head to
head with the ILEC. Cablevision's Lightpath division comes to mind here, as do
several of COX' and Comcast's metro entrees. But these, of course, are not based
on some RF exorcism device. Instead, they are standard fare, comparable to what
MFN/Abovenet or the local ILEC would install. I suppose that the Narad approach
works for limited numbers of corporate type accounts on the same segment, maybe
even more than I could envisage. I couldn't tell you exactly how well it would
scale.
Frank
On Mon, 31 May 2004 13:47 , 'Christopher J. Wolff' chris@bblabs.com> sent:
>
>All of these are great observations. So what's the cable HFC Achilles heel?
>
>-----Original Message-----
>From: frank@dticonsulting.com
[frank@dticonsulting.com','','','')">frank@dticonsulting.com]
>Sent: Monday, May 31, 2004 12:58 PM
>To: nanog@merit.edu; ''Christopher J. Wolff''; frank@dticonsulting.com
>Subject: Re: [url correction] Cable networks RE: best effort has economic
>problems, maybe OT
>
>Correcting a previous url error on my part.
>
>Narad's site is at:
>
> http://www.naradnetworks.com
>
>
>Sorry 'bout that, folks.
>
>Frank
>
>On Mon, 31 May 2004 11:30 , frank@dticonsulting.com> sent:
>
>>
>>Agree, this is a great discussion, akin to a recent Cook Report accounting
>of
>best
>>effort considerations. Several startups (now going into year two) have
>addressed
>>the cable-HF/C constraints you've mentioned. You may be interested in
>perusing
>>these two:
>>
>>http://www.narad.com
>>
>>Another, Rainmaker Technologies...
>>
>>http://www.rainmakertechnologies.com
>>
>>.... appears to have fallen on hard times while seeking later round
>funding. Not
>>sure of their disposition at this time, but doing googles on their name
>reveal
>>some good articles on their approach to using wavelets to improve bit gain
>over
>>black coax/fiber systems to homes and businesses.
>>
>>Metcalfe has financial backing hooks and input into Narad, and Mark E.
>Laubach of
>>COM21 fame (ATM over HF/C) heads up (headed up?) Rainmaker's technical
>pursuits.
>>
>>[[As an aside, I'm finding increased interest in corporate parks
>(especially
>those
>>that are boondocks-bound) where MSO fiber-based offerings are being
>seriously
>>considered for WAN access, both of the type discussed above and enterprise-
>>tailored rings coming off local head-ends.]]
>>
>>Frank
>>
>>
>>On Sun, 30 May 2004 08:47 , 'Christopher J. Wolff' chris@bblabs.com> sent:
>>
>>>
>>>Folks,
>>>
>>>This is a great discussion. I'm interested in understanding these types
>of
>>>limitations in the context of HFC cable networks. In my opinion, HDTV
>>>channel bandwidth (30mhz?) , increased demand for voip, and growing demand
>>>for IP connectivity is going to stress the cable network model as well,
>>>forcing cable operators to convert everything to IP before going out
>across
>>>the wire. Any input is appreciated.
>>>
>>>Regards,
>>>Christopher
>>>
>>
>>
>>
>>
>
>
>
>
