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Re: [802SEC] some 802 history is captured here

Hi Bob,   You may or may not recollect that I was the originator of the
FDDI-II Hybrid Ring proposal and the patent for that design was filed by CXC
Corporation on behalf of myself and Dr. Gary Nelson, who was my boss at that
time.  We presented that original proposal at the Santa Barbara Session of
X3T9.5 in February 1986. It was an instant hit and I was an active
contributor to the committee until CXC Corporation went out of business in
1987.  I rejoined the activity during the time I worked for MetaCom in RTP,
NC but sadly they were killed off on Black Monday (October 1987) and Mike
Teener (now active in 802.1) took over as the prime mover on that project.  

Thanx,  Buzz
Everett (Buzz) Rigsbee
7750 80th Place SE
Mercer Island, WA  98040-5912
(206) 236-2229

-----Original Message-----
From: [] On
Behalf Of Grow, Bob
Sent: Monday, July 27, 2009 3:34 PM
Subject: Re: [802SEC] some 802 history is captured here

When I started in 802 in 4Q1981, I was working on and looking for kindred
spirits for doing hierarchical networks (10 and 100 Mb/s, support packet
voice, consequently deterministic performance and the need to bridge between
speeds).  The 20 Mb/s scope was definitely a problem for that vision.  The
solution my colleagues and I at Burroughs were refining was a timed token

I'd originally invented the timed token protocol for an electrical CATV
technology based bus.  So, being applicable to both ring and bus, I proposed
the protocol to the Token DLMAC (soon to become 802.4 and 802.5).  It was
accepted for a few weeks.  Then I got a rude awakening to the politics of
standardization at the hands of IBM and others, with Token Ring changing
back to being based on the IBM Zurich protocol, but 802.4 retaining the
timed token protocol.

Sperry showed up in 802.5, but found it inhospitable for various reasons,
one being the speed issue.  They were though very open to any MAC protocol
that would work for their requirements (determinism, speed and reach).  

So, Sperry seriously engaged in X3T9.5 work.  When I arrived in X3T9.5 in
3Q1983?, I think they had already tagged their effort as FDDI.  The name fit
with the ongoing work on LDDI which as I recall was based on DEC's CI VAX
interconnect.  Sperry quickly bought into using the timed token protocol for
FDDI, and so a Burroughs MAC was hooked up with a Sperry PHY and the project
got traction.  DEC was still around because of LDDI, and they, HP and others
quickly got sucked into the work.  Chip companies joined and as well as too
many other companies, and progress ground to a snails pace complexity
increasing (especially in FDDI SMT).  Sad considering the capability of many
of the individual contributors involved.

Just as a tangent, some others at Burroughs had added an isochronous
interrupt capability to the timed token protocol and I proposed the whole
package at the beginning (which probably would have met the later FDDI-II
requirements, but others didn't see any isochronous need at that time).
When re-proposed a few years later for FDDI-II, the isochronous folk didn't
like it because it "complicated" slot interchange at the bridge (burst rate
of the isochronous data was much faster than the approach for FDDI-II).  IBM
TJ Watson independently invented a very similar interrupt and proposed it
later for FDDI follow-on, and some might remember another independent
invention and abortive (post gigabit?) CFI for adding similar interrupt
capability to Ethernet.

The isochronous capabilities that spawned FDDI-II were the same thing
driving 802.9.  Both had TDM bandwidth partitions for packet and isochronous
data, but the latter using Ethernet as the packet MAC protocol rather than
the timed token protocol for FDDI-II packet data.

802.6 also played with isochronous data ideas, so I don't recall our history
for focus on variable size packets being as pristine as Geoff recounted.

(Committee shopping to find a place to do your standard isn't new.)  

The scope of X3T9.5 from my perspective was clearly backend networks (now
would probably be called a Data Center network).  There was a need for long
links in back-end to remote disks and tapes outside the computer room
(archival, secure survivable backup, etc.)  So significant link lengths were
defendable for back-end applications, even though it allowed most everyone
to see FDDI's potential as a backbone LAN to connect 802 LANs.  (Where it
found its time in the market before Fast Ethernet squashed it.)

As Ethernet folk know, X3T9.5 also developed TP-PMD for FDDI, and they chose
to take the years of work on FDDI PHY, FDDI PMD, and FDDI TP-PMD as the
basis for the physical layer for Fast Ethernet (100BASE-FX and 100BASE-TX).
IEEE 802.3 consequently got faster time to market as well as establishing
the pattern for multiple future Ethernet speed increases.

So, the 802/X3T9.5 inter-relationship was pretty active.  And more than a
few people participated in both committees.

Pat, I don't remember the metro reach of 802.6 being a turf controversy with
X3T9.5, but I do remember it being a scope controversy.  The original 802
charter included reach assumptions, which 802.6 clearly intended to exceed.
I think all the controversy was internal to 802.  By then it was pretty
clear X3T9.5 was really developing a LAN (even though it still had back-end
network requirements), and consequently there was no interest in starting a
turf fight with 802 from the X3T9.5 side.  

I've occasionally joked that I might be the most promiscuous 802 participant
(802.4, 802.5, 802.6, 802.9, 802.11 and finally with gigabit settling in
802.3).  While prior to that on the X3 side also participating in FDDI,
FDDI-II, FDDI Follow On, and HiPPI.  With all those committees, details can
get blurred, so if others remember it differently we might be able to
clarify things together.


-----Original Message-----
From: ***** IEEE 802 Executive Committee List *****
[] On Behalf Of Pat Thaler
Sent: Monday, July 27, 2009 1:31 PM
Subject: Re: [802SEC] some 802 history is captured here

A bit of interesting history regarding the evolution of 802 scope is hinted
at by the mention of X3 at the end of the letter in the pdf.  X3 was working
on FDDI in X3T9.5 and the upper limit of 20 Mbps for 802 networks was to
keep us as LANs and leave higher speed MANs to them. I recall an exciting EC
meeting (back when I was in the peanut gallery) because the PAR for 802.6
was being considered which stepped on their toes. That added MAN to our
scope and eventually 802.3 also discarded the 20 Mbps upper limit for its

-----Original Message-----
From: ***** IEEE 802 Executive Committee List *****
[] On Behalf Of Paul Nikolich
Sent: Monday, July 20, 2009 11:06 AM
Subject: [802SEC] some 802 history is captured here

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list is maintained by Listserv.

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