Brad,
The
clause 45 register addressing was constructed so that it didn't interfere
with clause 22 register access. If 1000BASE-T devices can auto-negotiate, they
could use clause 22 defined registers for addressing that auto-negotiation
mechanism and use clause 45 registers for 10 Gig specific management.
The
only conflict one would have to resolve is in the electrical interface to the
management registers. Clause 22 specifies higher voltage than Clause 45. Given
current technology, one probably would want to use the Clause 45 electrical
specification.
Regards,
Pat
-----Original
Message-----
From: Booth, Bradley
[mailto:bradley.booth@intel.com]
Sent: Monday, February 24, 2003
7:57 PM
To: stds-802-3-10gbt@ieee.org
Subject: RE:
[10GBASE-T] EFM OAM...
Ahmet,
Valid points. Some may argue that EFM OAM
didn't exist when 1000BASE-T or 1000BASE-X were written, but that has not
prevented EFM OAM from having some affect on 1000BASE-X. When 802.3ae
was starting, 802.3ad (Link Aggregation) had not yet completed, but there
was a decision to support Link Agg in 802.3ae. The 10GBASE-T Study
Group will have to make decisions about what portions of 802.3, 802.3ae,
802.3af and 802.3ah that we feel we should support or at least consider
supporting moving forward. For example, do we use Clause 22 management
or Clause 45 management? If we use Clause 45 but wish to support
auto-negotiation to lower speeds, then we may need to consider supporting
Clause 22 access to Clause 45 registers. 802.3 is a living document,
so we need to be careful about what parts we do and do not want to consider
in our effort.
As
the Chair, I want to make sure we consider all aspects of creating a
standard, from the technical feasibility up to the management
requirements. All opinions are valid, and open discussion is a great
way that we make sure we haven't left stones unturned.
Thanks,
Brad
Brad, if this isn't an invitation to get one into trouble, I don't
know what is. In any case, my input would be that we need OAM no
more than 1000BASE-T does, so I'd favor leaving out of the scope of the
10GBASE-T PHY. If someone wants to implement some level of OAM in a
derivative PHY device or use MAC level OAM functions they're free to
do so.
Also, from my limited understanding of 802.3ah, OAM
for the PHY layer is TBD, so I don't think we can consider the
work being done in EFM as useful precedence at this
point.
-ahmet
Geoff,
Would you like to make a presentation to that
effect? :-)
I see the Study Group as having three options
related to OAM in our objectives:
1) state compliance with EFM OAM (and
therefore possibly use it in our effort)
2) state that EFM OAM is beyond the scope
of 10GBASE-T, excluding it from use within our
effort
3) say nothing, and leave the use of EFM
OAM capabilities up to those implementing the
systems
Which of the three options would you
prefer?
Would anyone else like to state a preferred
option?
Thanks,
Brad
Brad-
I would say
that
since...
the
same entity is likely to own both ends of the
link
AND
both
ends of the link are expected to be in the same
building.
AND
both
ends of the link are likely to be in the same room
that there is no
need for management beyond that required for existing enterprise
links.
Geoff
At 08:32 PM 2/18/2003 -0800, Booth,
Bradley wrote:
Study group members,
As some of you may
know, EFM (Ethernet in the First Mile or 802.3ah) has added
Operation, Administration and Management (OAM) capabilities to their
specification. Like 802.3af DTE power, the study group needs
to decide whether or not compliance with 802.3ah is within the scope
of our effort, and most specifically the OAM capabilities.
This relates to compatability with our existing standards. If
there is anyone that would like to make presentations for or against
compliance with 802.3ah or 802.3ah OAM, please let me
know.
Thank you,
Brad
Chair, 10GBASE-T Study Group
bbooth@ieee.org