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Re: last mile, regulatory incentives, etc


From: Jimmy Hess <mysidia () gmail com>
Date: Fri, 23 Mar 2012 22:59:23 -0500

2012/3/22 Masataka Ohta <mohta () necom830 hpcl titech ac jp>:
William Herrin wrote:

The entire optics is shared by all the subscribers sharing
a fiber.
Thus, the problem is collision avoidance of simultaneous
transmission, which makes PON time shared with L2 protocols.

Hm... i'm thinking one transceiver might malfunction and get
stuck/frozen in the  "transmitting pulse"  state, thus making
collision avoidance impossible, kind of like a shorted NIC on a shared
bus topology LAN,  if just one subscriber's equipment happens to have
the right kind of failure,  and that's neglecting the possibility of
intentional attack.

Passive optically-shared fiber networks don't sound so hot in that case.


So, you share fiber by having one guy control one wavelength (color,
e.g. red) and another guy control another wavelength (e.g. blue).
That's not a usual PON but WDN PON.

--
-JH


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