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Re: [EFM] Re: [EFM-P2MP] Point-to-Point plus Shared Media


I have a question of the service providers.

Isn't the "shared" function of the PON more of a simplex, single direction" 
type of traffic?  Correspondingly, isn't the P2P emulation a duplex, both 
directions, type of traffic.  Doesn't this make the functional 
inter-working with 802.1 different for the two different types of traffic?

My view of the "shared" functionality seems to be very much in conflict 
with how it has represented at the last meetings.  I think that the 
"service providers" need to get together and make a presentation at the 
next meeting that would include the "services" and the functional 
requirements of those "services".

Thank you,
Roy Bynum

At 04:55 PM 11/20/2001 -0300, carlosal@xxxxxxxxxxxxxxxxxx wrote:

>Two comments:
>1) John Pickens said:
> > I know there is a contingent within the working group that does not
> > consider it a requirement to access the single-copy-broadcast attribute
> > the media, so probably we should poll this question at some point.
>Although I'm the first to acknowledge that my opinion is *not*
>representative of all carriers (far from it :-), I can say that the
>single-copy-broadcast is one of the *great* potential advantages of using
>Ethernet PON in the access network. Of course, it all depends on whether
>will we be able to provide broadcast-based services such as digital video.
>I believe that many carriers will be of the same opinion.
>So my vote is already cast - single-copy-broadcasts are a requirement.
>2) Norman Finn's idea is really neat from a technical *and* political
>standpoint, as it sounds as a reasonable compromise between the two fields;
>however, I'm not sure that it's actually feasible in practice due to
>administrative reasons, as John pointed out. It is highly probable that
>most carriers will end up using only one of the modes.
>[For instance, this already happened with DSL; almost nobody uses the two
>transmission modes of DMT modems (interleaved and fast). Although it is
>technically possible to use the two at the same time, almost everybody uses
>only the interleaved one, mainly because of the complexity, and also
>because of potential compatibility issues]
>Anyway, just to explore the alternatives, we could deploy completely
>separate IP networks, each over a separate MAC address (of course this
>assume that we are going to run IP over Ethernet, but who bets otherwise?).
>Each IP network could 'opt' for some particular mode of operation.
>p.s. There are also some security issues that we should analyze in this
>case; the two kinds of traffic would be received at every node, and this is
>could pose a different security problem. Not sure about it, just wondering.
>Carlos Ribeiro
>CTBC Telecom