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RE: What is 802.3ae WAN-PHY?

Hi Dae, Hi Jonathan,

Thank you for your feedback.  Some of my comments are intersperced 
bellow.  Sorry for my short reply, but I am now trying hard to figure 
out pros and cons of the SONET framer approach and the XGENIE approach 
with the help of another valuable feedbacks from the SONET-framer side
(my thanks to Paul, Dave, and Roy).  I think I will be able to post 
the result in a few days.

At 1:16 PM -0700 00.4.8, Jonathan Thatcher wrote:
> I assume the following from what I have seen thus far:
> 1. To adopt this might not require 802.3ae to write a new set of
> line/path/etc management primitives.

I think at least we will not need re-write ITU-T G774 series where 
the management object of network element is defined.  As for ITU-T 
G707 where the SDH overhead bytes are defined and allocated, we 
need further investigation about how far we can make the mapping 

> 2. A direct mapping would allow the "WAN" and the "LAN" systems to link in
> a more direct way at, effectively, a lower level.
> 3. It permits greater flexibility in where we might choose to architect the
> SONET framer in order to optimize the solution. It might even permit
> multiple instantiations.

Good point.  If the SONET adopts the Ethernet packet adaptation with 
IPG transparency such as 64b/66b on SONET by Uni-PHY, Ethernet PHY can 
enjoy end-end path signaling without any mapping.  This is your 
muliple instatiations, right?

>> -----Original Message-----
>> From: Dae Young KIM [mailto:dykim@xxxxxxxxxxxxx]

>> Anyway, these bytes are only XENIE specific and imbedded into 
>> IPG. No mapping to
>> SONET overheads. XENIE management bytes are transferred 
>> trasparently over SONET to
>> the other end until you meet another XENIE.

I still reserve my final decision which would be supportive for 
full-SONET; 64/66 or EOS.  The latter don't support IPG transparency 
and hence here I provide the mapping.  

>> If you could somehow manage to push your XENIE (or only its 
>> features) into MAC or
>> RS(Reconciliation Layer), then thus management-enforced 
>> Ethernet MAC frames would
>> be able to be poured  directly into the SONET frame. 

As Rich has already responded, RS would be better than MAC for 
the instantiation.  Preserving MAC is clearly stated in five 

>> Osamu Ishida wrote:

Best Regards,

NTT Network Innovation Laboratories
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