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:
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
effort considerations. Several startups (now going into year two) have addressed the cable-HF/C constraints you've mentioned. You may be interested in
these two:
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
of best perusing 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