last mile, regulatory incentives, etc

Masataka Ohta mohta at necom830.hpcl.titech.ac.jp
Sat Mar 24 08:17:11 CDT 2012


Jimmy Hess 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.

That is a real problem harming healthy development of broadband
Internet.

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

Worse, as optical fibers are so cheap these days, SS (single star)
costs less than PON, because PON requires more complicated wiring.

Even worse, if people are deceived to recognize PON cheaper than
SS, it is impossible to have optical Internet in sparsely
populated area where optical Internet with SS is possible.

It can be said that PON was promoted by ILECs only to keep
their monopoly.

						Masataka Ohta



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