nanog mailing list archives
Re: Muni fiber: L1 or L2?
From: Masataka Ohta <mohta () necom830 hpcl titech ac jp>
Date: Fri, 08 Feb 2013 17:36:31 +0900
Jay Ashworth wrote:
As PON require considerably longer drop cable from a splitters to 4 or 8 subscribers, it can not be cheaper than Ethernet, unless subscriber density is very high.Oh, ghod; we're not gonna go here, again, are we?
That PON is more expensive than SS is the reality of an example contained in a document provided by regulatory body (soumu sho) of Japanese government. http://www.soumu.go.jp/main_sosiki/joho_tsusin/policyreports/chousa/bb_seibi/pdf/041209_2_14.pdf. Assume you have 4000 subscribers and total trunk cable length is 51.1Km, which is the PON case with example and trunk cable length will be identical regardless of whether you use PON or SS. The problem of PON is that, to efficiently share a fiber and a splitter, they must be shared by many subscribers, which means drop cables are longer than those of SS. For example, if drop cables of PON are 10m longer in average than that of SS, it's total length is 40km, which is *SIGNIFICANT*. Just as the last miles matter, the last yards do matter.
Yes, a PON physical build can be somewhat cheaper, because it multiplexes your trunk cabling from 1pr per circuit to as many as 16-32pr per circuit on the trunk, allowing you to spec smaller cables.
That is a negligible part of the cost. Cable cost is not very sensitive to the number of fibers in a cable. Masataka Ohta
Current thread:
- Re: Muni fiber: L1 or L2?, (continued)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 06)
- Re: Muni fiber: L1 or L2? Mikael Abrahamsson (Feb 07)
- Re: Muni fiber: L1 or L2? Scott Helms (Feb 07)
- Re: Muni fiber: L1 or L2? Mikael Abrahamsson (Feb 07)
- Re: Muni fiber: L1 or L2? Scott Helms (Feb 07)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 07)
- Re: Muni fiber: L1 or L2? Jay Ashworth (Feb 07)
- Re: Muni fiber: L1 or L2? Jason Baugher (Feb 07)
- Re: Muni fiber: L1 or L2? Mikael Abrahamsson (Feb 07)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 08)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 08)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 08)
- Re: Muni fiber: L1 or L2? Jean-Francois Mezei (Feb 08)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 08)
- Re: Muni fiber: L1 or L2? Robert E. Seastrom (Feb 08)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 09)
- Re: Muni fiber: L1 or L2? Robert E. Seastrom (Feb 09)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 09)
- Re: Muni fiber: L1 or L2? Jason Baugher (Feb 09)
- Re: Muni fiber: L1 or L2? Robert E. Seastrom (Feb 09)
- Re: Muni fiber: L1 or L2? Masataka Ohta (Feb 09)