Muni fiber: L1 or L2?

Masataka Ohta mohta at necom830.hpcl.titech.ac.jp
Sat Feb 9 11:41:48 UTC 2013


Robert E. Seastrom wrote:

>> Let's assume 4:1 concentration with PON.
> 
> Why on earth would we assume that when industry standard is 16 or 32?

That is because additional 4:1 concentration is usually at CO,
which does not contribute to reduce the number of fibers in a
trunk cable.

> 16 is a safe number.

Do you mean a splitter in field should be shared by 16
subscribers?

Then, with the otherwise same assumptions of my previous mail,
total extra drop cable length for PON will be 204km, four times
more than the trunk cable length.

Thus, it is so obvious that SS is better than PON.

OTOH, if concentration is 2:1 or less, it is, again, obvious that
SS is better than PON, because of extra complexity of PON.

So, 4:1 is the safe number to obfuscate lack of merit of PON.

If you can read Japanese or FTTH is serious business of you
worth hiring a translator of your own, you can find average
number of subscribers sharing a splitter in field is 3.68,
a little less than 4, from:

	http://itpro.nikkeibp.co.jp/article/COLUMN/20080619/308665/

						Masataka Ohta




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