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[EFM] Wavelength allocation

I've tried to send this message a few times over the weekend, but I didn't 
get through. I'm trying again, because this is a very important topic, 
looking from the carrier's perspective.

Most EPON proposals are P2MP. You have to use a sophisticated arbitration 
mechanism to control the use of the upstream channel. Although complex and 
initially expensive, DOCSIS did this before, and with high volume the cost 
of CPEs is driven down. However, the user is still concerned with the 
security (ok, we know it's almost impossible to tap the neighboor upstream 
signal, but go figure customer's mind :-). Also, the amount of bandwidth is 
limited by design. Any changes must be implemented by all elements in the 
give cable/fiber segment.

In the P2P EPON proposal, each customer gets their own wavelength. You have 
PON at the physical level, but a point-to-point connection at the upper 
layers. I believe this is the best of both worlds, because you have high 
speed, and you can provide dfferentiated services for some customers in the 
segment. You're not stuck with the technology of the traditional PON 
central node.

As the technology evolves, it's possible that we'll hit the technical 
limitations of the first generation EPON systems - the ones that are going 
to be deployed in the next months. In the cable industry, you use smaler 
segments to improve efficiency. Using P2MP EPON, you can do the same, but 
you can also start to deploy new wavelengths for the new services. In fact, 
it is possible to envision a scenario where you end up allocating a 
wavelength for every individual customer, turning your P2MP network into a 
P2P network.

Other applications can (and should) user their own wavelengths. The best 
example that comes to mind is broadcast video - it's much more efficient 
and less expensive to deliver it using a separate lamda, than trying to 
carry it over packets.

As it is, I would like the EFM standard to include a wavelength allocation 
policy. I haven't seen this discussed in depth; some presentations touch on 
this topic slightly. There is someone working specifically on this?

Carlos Ribeiro
CTBC Telecom