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RE: Cable networks RE: best effort has economic problems, maybe OT
From: <frank () dticonsulting com>
Date: Tue, 1 Jun 2004 20:32:16 -0500
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 accountingof besteffort considerations. Several startups (now going into year two) haveaddressedthe cable-HF/C constraints you've mentioned. You may be interested inperusingthese two: http://www.narad.com Another, Rainmaker Technologies... http://www.rainmakertechnologies.com .... appears to have fallen on hard times while seeking later roundfunding. Notsure of their disposition at this time, but doing googles on their namerevealsome good articles on their approach to using wavelets to improve bit gainoverblack coax/fiber systems to homes and businesses. Metcalfe has financial backing hooks and input into Narad, and Mark E.Laubach ofCOM21 fame (ATM over HF/C) heads up (headed up?) Rainmaker's technicalpursuits.[[As an aside, I'm finding increased interest in corporate parks(especially thosethat are boondocks-bound) where MSO fiber-based offerings are beingseriouslyconsidered 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 typesoflimitations 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 outacrossthe wire. Any input is appreciated. Regards, Christopher
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