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Re: Issues concerning 10GbE speed standards

It will help a great deal if you could point out specific aspects and approaches
where an Ethernet extended to support all of the existing common carrier O&M
requirements, encapsulated within the existing Sonet/SDH structure, running over
existing OC192/STM64 facilities, will actually come out costing significantly
less that the current solution?
- Peter

Roy Bynum <rabynum@xxxxxxxxxxx> on 06/20/99 07:34:08 AM

Please respond to rabynum@xxxxxxxxxxx

Sent by:  Roy Bynum <rabynum@xxxxxxxxxxx>

To:   wthirion@xxxxxxxxxx
cc:   stds-802-3-hssg@xxxxxxxx, stds-802-3-hssg-speed@xxxxxxxx (Peter
Subject:  Issues concerning 10GbE speed standards

Walt, et al,

The issue of speed is one of economics.  The existing GbE standard does
not allow for any operations support for the optical fiber facility.
This makes GbE very expensive to maintain and support over a MAN/WAN
environment.  The cost of ownership of GbE will prevent it from having a
masive impact directly on the cost of MAN and WAN data communications.

Common carrier protocols, such as DS1/DS3/SONET/SDH have operations and
maintencance functionality incorporated in the overhead of the
protocol.  DS1 and DS3 have a subcarrier that provides remote and
reverse signalling outside of the transport "payload".  This allows
carriers to troubleshoot and maintain remote systems without haveing to
dispatch someone for every little issue.  In some respects, GbE fails to
meet the 802.3 functional requirements for interoperation with common
carrier systems.

1000BaseSX and 1000BaseLX are optical networking standards.  Whether
this was the intention or even the perception of the 802.3 working
group.  The working group did not include any support for operations or
maintenance in the optical domain for this protocol.  The functional
operations of copper LAN facilities are well understood by the 802.3
working group, but when you get beyond multi-mode, 850nm, optical
transport, it is no longer a LAN, it is a WAN.  Some will say that 30km
is a MAN, not a WAN.  If you apply the same function processes
distictions to optical systems that are applied to copper systems, you
will discover that a MAN is actually a WAN within a single central
office domain. When I was actively working on Ethernet, when it left the
building, it was no longer a LAN, it was a WAN.

In order for 10000BaseX to support MAN/WAN systems within common carrier
facilities, common carrier operations and maintance support must be
within the protocol.  SONET/SDH are the current, and most widely
deployed transport protocols within the common carrier domain.
SONET/SDH use the transport overhead to provide that functionality.
That functionality allows the common carriers to reduce the operations
and support costs for the fiber optic transport systems, and thus lower
the overall costs passed on to the end users.  This will be the economic
breaking point for 10GbE.  Can it directly support the fiber optic
transmission system?  Is there any reason why it should not be able to
directly provide operations support for the optical fiber systems?

A second economic issue of speed for 10GbE is one of utilizing existing
technology and standards at the ~10Gigabit speed range.  A masive
install base of facilities and support already exist for OC192/STM64 on
a global scale.  Optical amplifers, signal and clock recovery
regenerators, and other systems are already in place to carry
OC192/STM64 signals in metropolitan as well as wide are networks.  I
would not want to contemplate the economic impact of having to install
totally seperate technology to support 10GbE.  If it can not use the
existing ~10Gb technology and facilities, Other than "dark fiber", 10GbE
will have to be installed over a totaly new, and totaly seperate
facilities.  Is there any reason why 10GbE should not support and make
use of the existing ~10Gb transport facilities?

I hope that this message has not been too long.  As an employee of a
common carrier company, I have a recognizable vested interest in looking
toward 10GbE as a major economical alternative to existing data tranport
technolgy, such as TDM or ATM.  I have almost 20 years of designing,
installing, and supporting LAN, MAN, and WAN systems.  I have seen the
economics change as more self-supporting protocols and technologies have
become available.  The key is to provide a protocol that allows remote
operations support, which reduces the number of "warm bodies" that are
required to support the systems.  This is what I am asking for.  Is
there any reason why this can not be done?

                         Thank you,
                         Roy Bynum
                         MCI WorldCom