Word to dropping docsis science on NANOG. On Feb 2, 2013 3:34 PM, "Scott Helms" <khe...@zcorum.com> wrote:
> > I hope I said "E7"; it's what I meant to say. Yes, I wasn't going to > > stop at Calix; I'm just juggling budgetary type numbers at the moment; > > I'll have 3 or 4 quotes before I go to press. It's a 36 month project > > just to beginning of build, at this point, likely. > > > > Assuming I get the gig at all. > > > > The E7 is a good shelf, so that's a decent starting point. I'd also talk > with Zhone, Allied Telesys, Adtran, and Cisco if for no other reason but > get the best pricing you can. I'd also focus much more on your cost per > port than the density since your uptake rate will be driven by economics > long before port density and how much space your gear takes becomes an > issue. > > > > > > 2) I have no idea who told you this, but this is completely and utterly > > > incorrect in nationwide terms. If you have a specific layer 3 provder > > > in mind that tells you they want a GPON hand off then that's fine, but > > > ISPs in general don't know what GPON is and have no gear to terminate > > that > > > kind of connection. > > > > Other people here, said it. If nothing else, it's certainly what the > > largest nationwide FTTH provider is provisioning, and I suspect it serves > > more passings than anything else; possibly than everything else. > > > > I'm not sure what you mean by this. The largest PON offering in the US is > Verizon's FIOS, but AFAIK they don't interconnect with anyone at layer 2 > and their layer 3 fiber connections are either Packet Over SONET, Gig > E(most common), or very occasionally still ATM. I have heard of a few > instances where they'd buy existing GPON networks but I've never heard of > them cross connecting like this even with operators that they do > significant business with in other ways. > > > > > > But it doesn't matter either way, except in cross-connects between my MDF > > and my colo cages; except for GPONs apparent compatibility with RF CATV > > delivery (which I gather, but have not researched) is just > block-upconvert, > > I don't care either way; there's no difference in the plant buildout. > > > > This is not correct. DOCSIS is an MPEG stream over QAM or QPSK modulation > and there is nothing about it that is compatible to any flavor of PON. In > fact if you look at the various CableLabs standards you'll see DPoE ( > http://www.cablelabs.com/dpoe/specifications/index.html) which lists how a > DOCSIS system can inter-operate and provision an PON system. If you look at > the two largest PON networks (FIOS and Uverse) you'll see the two different > approaches to doing video with a PON architecture. Verizon is simply > modulating a MPEG stream (this is block compatible to a cable plant, in > fact its the same way that a HFC network functions) on a different color on > the same fiber that they send their PON signalling. ATT takes another > approach where they simply run IPTV over their PON network. I've listened > to presentations from Verizon's VP of Engineering (at that time) for FIOS > and he said their choice was driven by the technology available when they > launched and they did modulated RF over their fiber instead of IPTV because > that technology wasn't as mature when they started. Verizon's approach may > be what someone was thinking of when they said that PON was compatible to > cable signaling but that's not how it works. > > > > > > Cheers, > > -- jra > > -- > > Jay R. Ashworth Baylink > > j...@baylink.com > > Designer The Things I Think RFC > > 2100 > > Ashworth & Associates http://baylink.pitas.com 2000 Land > > Rover DII > > St Petersburg FL USA #natog +1 727 647 > > 1274 > > > > > > -- > Scott Helms > Vice President of Technology > ZCorum > (678) 507-5000 > -------------------------------- > http://twitter.com/kscotthelms > -------------------------------- > > > > -- > Scott Helms > Vice President of Technology > ZCorum > (678) 507-5000 > -------------------------------- > http://twitter.com/kscotthelms > -------------------------------- >