Dear Harmen,
My question to service providers are
really that, to the
service providers -- these may include some of the other target
markets you mentioned. 802.4 was a great technology that
no one used. 802.5, while IEEE stds, never
achieved broad
interoperability in the industry and did get displaced w/
10BASE-T.
FDDI was a great backbone technology that actually got used, until
Fast Ethernet switches displaced it. All of these technology wanted
to be the dominant technology that Ethernet is today
once it grew up,
but it did not.
I could say the same thing about RPR. It
could take over the
future networking as the preferred standard
everywhere; then again,
it may not. RPR is great
technology for packet-on-ring, coat-tailing
off of successes of SONET for TDM. So if SONET service ring
is
preferred method for Metro distribution, RPR ring may do the same
for
the packet delivery in Metro, and its extensions as the backbone to
the Ethernet-First-Mile technology. All other applications,
while
appropriate and possible, is hard to justify with real numbers.
Also,
I do not want to solve the problem that has been solved (and one
of
the 5 criteria, uniqueness, addresses this as well). We ought
to
optimize RPR for the clear application(s)
we used to justify it.
At this point, I have NO vested interest in
influencing the
standard to fit any implementation. I hope you and readers take
my
opinion as it reads -- do not optimize the standard for <~5% of
the
market, if it is at the risk of higher
cost(complexity, interoperability,
etc, etc) or scalability.
regards,
Yong.
============================================
Yongbum "Yong"
Kim Direct (408)922-7502
Technical
Director Mobile (408)887-1058
3151 Zanker
Road Fax
(408)922-7530
San Jose, CA 95134
Main
(408)501-7800
ybkim@xxxxxxxxxxxx
www.broadcom.com
============================================
Dear Yong
If you only ask service providers whether they
would like to support lower speed rings, you not really ask the market that
I addressed in my mail. That market has very much to do with communications,
but it is not the target of service prioviders. It is the broad market
of future multimedia communications mainly in facilities outside the
area of network operators and service providers. It is complementory to
802.3 networks, it is the world that previously was addressed by 802.4,
802.5, and FDDI. I do not really understand why that market would not be of
interest to IEEE 802.17. Why should those areas live outside the standard,
when they perfectly fit to resilience and QoS. New standard
neccessary?
Additionally addressed market:
rings and backbone rings for small offices,
hotels, major stores, small business centers, hospitals, companies, campus
areas, manufactury plants, industrial plants, small public access areas,
ships, airplaines, cars, interconnection of base stations of wireless
networks, etc., etc.
Best regards
Harmen
Yongbum Kim wrote:
Dear Harmen,
Related to the on-going preemption discussions
and how
high priority, low-latency & jitter is handled, I agree
that high speed RPR ring does not need preemption, but
the
lower speed one does.
I
would like to go back to "broad market potential"
requirements,
and would like to hear from the Service Provider
community on this
subject.
How many of the rings in
the metro that already has OC3
~ OC12
rings in a SONET infrastructure will be retrofitted
w/ RPR for packet services?
My assumption in this had been that
if a vendor installs new
equipment, it would be the latest and
fastest available box, because
installation and upgrade cost
out-weigh box cost. So the percentage
of the retrofit market
is relatively minimal. If this is the case,
lower speed MAC
behavior could live outside of the standard. If this
is not
the case, then we must define a single preemption behavior
for all
speeds of operation (again the second if, if the group
wants to
entertain the objective of supporting this high priority
low
latency & jitter class).
Would
someone from the Service Provider community provide some
feedback
on this retrofit market?
regards,
Yong.
============================================
Yongbum
"Yong" Kim Direct
(408)922-7502
Technical Director
Mobile (408)887-1058
3151 Zanker
Road Fax
(408)922-7530
San Jose, CA 95134
Main (408)501-7800
ybkim@xxxxxxxxxxxx www.broadcom.com ============================================
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Prof.Dr.
Harmen R. van As Institute of
Communication Networks
Head of
Institute
Vienna University of Technology
Tel
+43-1-58801-38800
Favoritenstrasse 9/388
Fax
+43-1-58801-38898
A-1040 Vienna, Austria
http://www.ikn.tuwien.ac.at
email: Harmen.R.van-As@xxxxxxxxxxxx
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