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RE: [EFM] EFM aggregation P2P v EPON




Hi Bob,
	Thanks for pointing out the flaw in my argument, but I stand by it.
Even P2P GigE with 10GE uplinks would require  aggregation in any practical
access network implementation. And even if you could do 1:1 aggregation
ratio but that would just push the aggregation point further upstream. If
you were to implement the 1:1 aggregation ration all the way between
endpoints the system would essentially reduce back to the TDM network. I
will concede that PON does limit tuning flexibility aggregation ratio, and
in cases where this is important P2P will win. But in most cases it will not
be an issue.



-----Original Message-----
From: Bob Barrett [mailto:bob.barrett@fourthtrack.com]

Dear Mike

I think there is a fundamental floor in the logic here. The aggregation
ratio (at the CO or POP box) is an implementation specific parameter, and
can be tuneable via management from 1:1 (no grading), down to whatever is
required. It depends on what the implementer is capable of implementing, and
what the customer requirements turn out to be.

Bob Barrett
bob.barrett@fiberintheloop.com

-----Original Message-----
From: owner-stds-802-3-efm@majordomo.ieee.org
[mailto:owner-stds-802-3-efm@majordomo.ieee.org]On Behalf Of
mike.obrien@alloptic.com
Sent: 08 June 2001 21:18
To: stds-802-3-efm@ieee.org
Subject: RE: [EFM] RE: Relative OSP Costs of PON vs. P2P



Pat,
	P2P may offer higher bandwidth from the subscriber to the CO than
PON, however it must perform some aggregation to it's upstream provider. A
P2P box with 32 1000Mbps subscriber links will not have 32 x 1000Mbps of
upstream links. PON does the 'aggregation' at the splitting point. Overall,
the PON subscriber will see essentialy the same bandwidth as P2P subscriber.


-----Original Message-----
From: Kelly, Pat [mailto:pat.kelly@intel.com]

Bob,

Sorry if I'm missing something.  I understand that PON systems can burst to
higher rates, but a 32 subscriber, one wavelength/direction PON should only
be able to provide 1000Mbps/32 or ~30Meg/subscriber (assuming 100%
efficiency).  This is much closer to VDSL than P2P at 1000Mbps/subscriber.

Of course, PON has significant advantages over VDSL (higher aggregate data
rate, upgradeability, video broadcast capability, etc.), so it should be a
very compelling comparison.

Pat

~~~~~~~~~~~~~~~~~~~~~~~~
N. Patrick Kelly
Director of Engineering
Networking Components Division
Intel Corporation
(916)854-2955
~~~~~~~~~~~~~~~~~~~~~~~~

 -----Original Message-----
From: 	Lund, Bob [mailto:blund@opticalsolutions.com]
Sent:	Friday, June 08, 2001 11:29 AM
To:	'Kelly, Pat'; 'Francois D. Menard'; gerry.pesavento@alloptic.com;
CarlisleRS@corning.com; stds-802-3-efm@ieee.org
Cc:	DuX@corning.com; FengW@corning.com; JayJA@corning.com;
KunziAL@corning.com; MusgroveKD@corning.com; JPropst@services.corning.com;
ShanemanK@corning.com; CSweazey@services.corning.com
Subject:	RE: [EFM] RE: Relative OSP Costs of PON vs. P2P

I don't think PON and VDSL provide similar levels of bandwidth.

Commercial VDSL systems feed curbside nodes with 155 - 622Mbps and
distribute asymetric bandwidth with a max of around 25Mbps per set of
twisted pair wires. Nodes typically serve around 30 subscribers. I've not
seen any developments that suggest that the 25Mbps max will go up
substantially.

Commercial PON systems provide 155 - 1000Mbps to a passive optical splitter
that, in turn, feeds up to 32 subscribers, each with 155 - 1000Mbps of
bandwidth. Bandwidth management protocols enable service providers to
control how much of the aggregate PON bandwidth is used by any subscriber.
PONs also provide greater upstream bandwidth than VDSL systems. PONs can
employ higher clock rate optics and/or CWDM to increase the amount of
bandwidth to higher rates, e.g. 4 wavelengths would provide 4x the
bandwidth.

Bob Lund
Chief Technical Officer
Optical Solutions Inc.


> -----Original Message-----
> From:	Kelly, Pat [SMTP:pat.kelly@intel.com]
> Sent:	Friday, June 08, 2001 12:13 PM
> To:	'Francois D. Menard'; gerry.pesavento@alloptic.com;
> CarlisleRS@corning.com; stds-802-3-efm@ieee.org
> Cc:	DuX@corning.com; FengW@corning.com; JayJA@corning.com;
> KunziAL@corning.com; MusgroveKD@corning.com; JPropst@services.corning.com;
> ShanemanK@corning.com; CSweazey@services.corning.com
> Subject:	[EFM] RE: Relative OSP Costs of PON vs. P2P
>
>
> PON vs. VDSL seems to be a more logical comparison than P2P vs. VDSL
> because
> PON and VDSL provide similar levels of service, i.e. bandwidth.
>
> ~~~~~~~~~~~~~~~~~~~~~~~~
> N. Patrick Kelly
> Director of Engineering
> Networking Components Division
> Intel Corporation
> (916)854-2955
> ~~~~~~~~~~~~~~~~~~~~~~~~
>
>  -----Original Message-----
> From: 	Francois D. Menard [mailto:f.menard@muni-ims.qc.ca]
> Sent:	Thursday, June 07, 2001 6:40 AM
> To:	gerry.pesavento@alloptic.com; CarlisleRS@corning.com;
> stds-802-3-efm@ieee.org
> Cc:	DuX@corning.com; FengW@corning.com; JayJA@corning.com;
> KunziAL@corning.com; MusgroveKD@corning.com; JPropst@services.corning.com;
> ShanemanK@corning.com; CSweazey@services.corning.com
> Subject:	RE: Relative OSP Costs of PON vs. P2P
>
>
> > As you can see from the graph, the PTP vs PTMP costs are sensitive to
> distance - SBC calculated PTMP is close to the same at short distance, and
> 50% the cost at >5 km.  I'd like to know more about what is behind SBC's
> data (if it includes equipment costs, I think so). I noticed that neither
> you nor Martin Adams mentioned distance; an important variable.
>
> I would like to know to which extent, cost of P2P has been found to be
> more
> extensive, considering that active equipments could be installed in the
> same
> manner than for VDSL in the street-end cabinets.  I believe that OCCAM is
> doing this for xDSL. Aggregating residential P2P on giant fibre bundles
> may
> work in Japan due to house densities, but it is more complex in
> North-America, however still remains a serious possibility.  I would
> rather
> see P2P compared to VDSL before P2P is compared to PON.
>
> Fundamentally, PON will be subject to the same myriad of problems that
> open
> access on cable modem plant is subjected to today, which are high-cost
> terminals, which can potentially screw up your neighbor's service were
> they
> going to become defective.  This has important implications on
> architecture
> and policy for third party access.  Suffice it to say that such problems
> are
> easily solved in P2P, and that I do not believe at all in comparing costs,
> while forgetting about estimating the costs of implementing third party
> access.
>
> -=Francois=-
>