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[ih] Secret precedence schemes back then


Geeze, nice to know somebody was watching. The fuzzies could do 
encapsulation, too, which is how HW and I had ARPAnet adresses at home.  
I was something liek host 2 on net 29 via the Mitre IMP and a foreign 
exchange line to Maryland. One of the first things I said to Steve Wolff 
on accepting the NSFnet job was that NSF specifically fund the gated 
project, as I viewed that as crucial to the success of the project, and 
so he did.

You might have notices a scurry back then about mapping RIP metric to 
and from Hello metric. Somewhere there is a postion paper on that and 
the issue of avoiding loops. There should have been a paper on that. The 
ARP gimmick you mentioned was used at UDel to launch UDel traffic and 
fuzzie traffic on the same wire. The Ethernet interface at the time was 
a monster $3000 board. The IMP interface was almost as much.

The last remaing fuzzball is in my basement. The original PDP11 code yet 
spins on a disk here. Someday somebody migh enjoy lighing it up in 
simulation. Meanwhile, I am having too much fun becoming a serious space 
nut and launching NTP on NASA space missions. See 
www.eecis.udel.edu/~mills/proximity.html. More to come, as my contract 
has just been renewed. Oh yeah, I have a contract for the second edition 
of my book. Suchis life in retirement.


Louis Mamakos wrote:

>On Wed, Jan 28, 2009 at 12:04:12AM -0800, Mike Padlipsky wrote:
>>At 08:04 PM 1/27/2009, Jack Haverty wrote:
>>>Also, hardware was severely limited.  I remember one router, connecting
>>>ArpaNet and Satnet, which at one point had only enough memory to buffer
>>>exactly ONE packet.  So there wasn't much question of how to handle
>>>priority in the "queue".
>>this point deserves particular emphasis.
>>while i didn't know your gateways were that minimal, i was keenly 
>>aware of the hardware limitations of the 'fuzzball' [and it might be 
>>nice if dave gave a rundown on just what the fuzzballs were for the 
>>benefit of newcomers ... and oldtimers who've forgotten], and any 
>>analogy between them and contemporary 'ISPs' must founder on 
>>precisely that point: today's hardware is so much more capable than 
>>'yesterday's' that any attempt to reason by analogy to what used to 
>>be licit is, i submit, a flagrantly false analogy.
>While at the University of Maryland in this era, we had few (herd?
>gaggle?) of fuzzballs and they probably were more capable than some of
>the BBN LSI-11 routers between the ARPANET and MILNET at the time.
>It's probably a little hard to imagine, but budgets and process were
>difficult at the time, and the community took up a collection to
>replace the LSI-11/23 CPU boards in those BBN routers with the fancy
>new LSI-11/73 CPUs!  I know that we at UMD "lent" a CPU board or two,
>as did some others at the time.
>Never got 'em back, but that's OK.  The inventory tags were on the
>outside of the chassis :-)
>I'm sure Dave will chime in, but as I recall there's a couple of very
>nice papers floating around on the Fuzzball system.  These days, you
>could have your very own, running inside a PDP-11 emulator at well
>over native speed.  Back in the day, we had fuzzballs running on
>LSI-11/2, LSI-11/23 and LSI-11/73 (floating point, and everything!)
>Q-bus systems.
>The fuzzballs used the "HELLO" protocol for their internal routing,
>which was a distance-vector protocol based on delay.  It also had the
>side-effect of being able to synchronize clocks and was the first step
>down the road to NTP, which consumed Dr. Mills for a couple of decades
>to come.  While at UMD, Mike Petry and I built a HELLO implemention
>for a couple of differnet platforms.  Mike did the original
>implementation in GATED I believe, and I included one in the UNIVAC
>1100 TCP/IP implementation that we had built.  Later, you could use
>HELLO in your Cisco routers.
>Of course, the fuzzballs were the first to tick NTP.
>An interesting contrast to what you typically see today is that
>fuzzballs had IP addresses associated with logical hosts (and there
>could be one or more nesting inside any given fuzzball).  Network
>interfaces didn't have a strong notion of an IP address of their own,
>at least in the sense of what you see today.
>At UMD, we did a really early Ethernet implementation for the
>fuzzballs, with an InterLAN ethernet controller and building an ARP
>subnetwork driver.  Because of the Fuzzball's notion of logical host
>addressing, the ARP implementation sort of naturally did proxy-ARP,
>though I didn't really recognize the novelty of that at the time.
>Louis Mamakos