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Re: What is 802.3ae WAN-PHY?

Dear Dave, Dear Roy,

Thank you for your feedback and corrections.  I would be pleased if 
you could keep in mind that we had better use interoperable words 
here in LAN community.

At 4:06 PM +0900 00.4.9, Osamu ISHIDA wrote:
 At 1:58 PM -0500 00.4.10, David Martin wrote:
 At 11:18 AM -0500 00.4.9, Roy Bynum wrote:

I have changed 'SONET-lite' into the word 'SONET-framed', and removed 
the word 'almost' from the overhead access of SONET.  I hope in this 
time this table suits your taste.
  --------------- --------------- ------------ ----------- ------
  expression      Overhead access CLK Accuracy CLK Jitter  Std.
  --------------- --------------- ------------ ----------- ------
  SONET           full            < +/-20ppm   SONET spec. T1.105
  SONET-compliant reduced         < +/-20ppm   SONET spec. T1.416
  SONET-framed    much reduced    < +/-100ppm  ??????????  ??????
  --------------- --------------- ------------ ----------- ------
  Here I assume that SONET-framed equals WAN-PHY with SONET framer 
  proposed in 802.3ae.

I have assumed that we agreed on the following two facts since I have 
received no objections;

(1) There is no SONET-framed PHY standard at present.  All SONET or 
    SONET-compliant equipment at present, including the emerging 
    non-muxing LTE, should meet +/-20ppm CLK accuracy and SONET 
    jitter spec.

(2) Pointer manipulation mechanism in SONET framer itself has 
    the potential to accommodate the CLK difference up to +/-320ppm.

Next what I would like to agree with you is the following;
  ---------------------- ------------------------- ------------ -----------
  expression             SONET function            CLK Accuracy CLK Jitter
  ---------------------- ------------------------- ------------ -----------
  old active transponder Section termination       < +/-20ppm   SONET spec.
  new active transponder Section&Line termination  < +/-20ppm   SONET spec.
  ---------------------- ------------------------- ------------ -----------
  Here I assume that new active transponder equals 'the emerging non-muxing 
  LTE' and hence equals Ethernet Line Terminating Equipment.  According to 
  above (1), I have assumed that both transponders should be SONET or SONET-

Why there are 'old' & 'new' active transponders?  This is because I have 
found that the definition of the active transponder seems to be waved;

old active transponder: see page 12 in
new active transponder: see page 35 (last page) in

As far as I know, most of the install-base active transponders 
are old type; only Section termination is performed.  This implies that 
the old active transponder equals SONET regenerator; no pointer 
manipulation mechanisms, no clock domain exchange.  This is a SNYCHRONUS 
regenerator; it is designed to guarantee its performance under +/-20ppm 
CLK accuracy specification.

Please let me know if this is a wrong observation.

What Mr. Gary Nicholl and I have asked repeatedly is that, since 
SONET-framed PHY is not SONET-compliant, you have no guarantee for 
the direct connection to these install-base old active transponder.  
It may work, but it may not work.  The old active transponder only 
follows the SONET or SONET-compliant +/-20 ppm specifications.

Another unclear point is who will define the ELTE specification 
at the Ethernet side (+/-100ppm).  Roy said that it would be soon 
defined by the other standard bodies, but Paul said ANSI would not.  
At 11:18 AM -0500 00.4.9, Roy Bynum wrote:
At 3:25 PM -0700 00.4.10, Paul Bottorff wrote:

In this situation, I could not believe that ELTE would be defined 
outside IEEE802.3ae unless SONET-framed PHY keeps +/-20ppm spec.

Have I mis-understood you? Can you please shed more light on
something I'm missing?

Best Regards,
Osamu Ishida