|Thread Links||Date Links|
|Thread Prev||Thread Next||Thread Index||Date Prev||Date Next||Date Index|
Our WAN PHY proposal uses the traditional +/-100ppm clock tolerance spec
of Ethernet. An ELTE would have a matching WAN PHY interface. The SONET
side of the ELTE will have an ITU/ANSI interface. Within the ELTE the clock
domain adaptation is performed using traditional SONET pointer processing.
Previous material has shown this is feasible. Please refer to
for more background. Thank-you.
David W. Martin
+1 613 765-2901
+1 613 763-2388 (fax)
From: Osamu ISHIDA [SMTP:ishida@xxxxxxxxxxxxxxxxxxx]
Sent: Friday, April 07, 2000 12:55 PM
To: Roy Bynum
Subject: Re: What is 802.3ae WAN-PHY?
Yes, I am assuming that the ELTE has something to do with Ethernet.
As I understand, the emerging non-muxing LTE requires SONET-
compliant input. I would like to remind you that at present I see no
SONET-lite standard in the real world.
Therefore, at least you need to customize the Ethernet side of the
non-muxing LTE to accomodate +/-100ppm SONET-imcompliant input.
I don't believe this customization makes sense because;
(1) it will bring nothing other than confusion, as Jay and Gary has
(2) There seems to be little cost advantage in +/-100ppm as Nevin has
Please do not force us to stick in SONET framing optimized for the
legacy synchronous transport systems.
You are free to invest both the SONET-imcompliant PHY and the ELTE,
but please understand that there are other carriers who must compete
with each other and hence require inexpensive future-proof OAM&P
signaling for datacom WAN. To drive it, I will propose SONET-
compatible XGENIE that enables us to carry SONET overhead bytes or
its equivalence without using the SONET framing. I don't think
this is a full greenfield development; just a kind of 1:1 mapping
between XGENIE ordered sets and SONET overhead bytes.
At 2:47 PM -0500 00.4.6, Roy Bynum wrote:
> Are you making the assumption that ELTE has anything to do with Ethernet?
> ELTE is a fake name that was used by the nomenclature group to as a place
> holder for a non-muxing LTE. The ELTE is refereeing to the new class of
> SONET/SDH optical switch gear that has been developed specifically to
> support high bandwidth concatenated services. There are several telephony
> vendors that are developing this equipment with the view to start deployment
> this year to support the OC192C/STM64C Packet Over SONET/SDH interfaces for
> Internet Routers.
> Please make the assumption that SONET framing will be used. Otherwise it
> will require a full greenfield development cycle and extended deployment
> cycle for the long haul transport systems. This is in violation of the
> objective to use existing technology where ever possible.
> Thank you,
> Roy Bynum
> ----- Original Message -----