[LINK] NBN layer 3 services

[Paul Brooks]

I'll wade in on this without commenting on the cisco position:

 
Richard Chirgwin wrote:
> The Comms Alliance reference model for the NBN supports *both* PON and 
> direct fibre.
>
> But really, given the stated aim of the NBN is covering 90% of the 
> population, a 20km footprint is easily enough. If at some point the 
> remaining 10% gets fibre, direct fibre will still be an option (but we 
> will never get fibre-to-100%).
>   
The limitation of 20km for PON is an error. G-PON at least has a range 
of up to 40km-60km depending on which vendor you listen to.
However, the closest endpoint and the furthest endpoint must be 
different by no more than 20km, due to timing limitations. If the 
closest end-point is 30km from the OLT, then the furthest could be up to 
50km distant, for example.
(However, video-over-RF-overlay imposes shorter distance restrictions, 
if that is a option to be deployed).
Other PON systems may have similar distance coverage, I can't recall at 
the moment.

And yes, the model supports direct fibre, for those endpoints who cant 
or wont be served by a PON.


>
> Returning to MPLS, I can't consider it an immature technology. I suspect 
>   
On MPLS, I'll point out the current Comms Alliance wholesale service 
description as a transparent Layer2 ethernet pipe ala MEF E-LINE and is 
completely transparent to ethertype.
It should just as easily transport MPLS-over-ethernet frames (ethertype 
0x8847/0x8848) as it can transport IPv4, IPv6 or even Appletalk frames 
if one so desires.

Paul (speaking for himself).