last mile, regulatory incentives, etc

Sat Mar 24 03:59:23 UTC 2012

2012/3/22 Masataka Ohta <mohta at 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