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[802.3ae] Wan Interface Sublayer difference from IETF POS


A major difference between IETF Packet Over SONET (POS) interface and the 
WAN PHY is that the POS interface was originally intended to be a client on 
a SONET transmission node and electrically multiplexed along with other 
client signals.  As a tributary client on a transmission node, it has to 
adhere to all of the specifications of a SONET transmission client.

It is not until OC192c POS, that it becomes a peer on the DWDM 
network.  Ironically, there are no specifications for a transmission 
service peer on a DWDM network.  10GbE WAN PHY is the first data 
communications protocol that is designed to operate as a peer on a DWDM 
service network.

This leads to some confusion about what the specifications need to be, 
because the transmission services standards deal only with client signal 
multiplexing services types of specifications.  The closest that I have 
seen for a specification of a non-multiplexing LTE is the specifications 
for a "Class B" regenerator in GR 253, and that isn't very much.  I have 
not heard of a set of specifications for optical service systems that do 
not include support for electrically multiplexed client signals.  Even the 
ITU OTN is an electrically multiplexed client service architecture.   If 
you want to make a real difference and go to T1X1 and get them to consider 
a set of specifications for optical peer level services that does not 
include support for electrically multiplexed client signals.

Thank you,
Roy Bynum

At 05:17 PM 8/27/01 -0400, Gary Nicholl wrote:

>One difference might be that OC-192c POS interfaces are fully compliant to 
>SONET/SDH jitter specifications (in terms of generation, transfer and 
>tolerance). The two parameters that are important with regard to interop 
>with long haul DWDM systems are obviously jitter generation and jitter 
>tolerance. If I understand correctly the 10GbE WAN PHY is not currently 
>aligned with SONET/SDH jitter specs. Any thoughts about the impact of this 
>on the interop with long haul systems ? I guess it was always my 
>understanding that one of the functions of this mysterious ELTE was to 
>convert from WAN PHY jitter specs to SONET/SDH jitter specs?
>Gary Nicholl .............