North American Network Operators Group

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Re: Internet II is coming...

  • From: Sean Doran
  • Date: Wed Oct 09 17:45:40 1996

| I suspect that they will be going completely switched and have very few 
| total points on the whole network (depending on what configuration they 
| go to). A network of OC12s or OC48s in a redundant star will  have 
| significant performance benefits because 1) no routing, or very symmetric 
| routing. 2) very low latency <8ms coast to coast I'd suspect. 3) priority 
| queues, quality of service, reserved bandwidth, etc. 

#0: well, nobody's physical topology is shaped like a redundant star.
    at very fast rates, for (2) above in particular, having the network
    topology follow rights-of-way is a good plan

#1: *something* somewhere has to do routing, and has to know the
    full details of what the topology looks like and make decisions
    based on that information and any constraints.  Problem A in
    the current Internet is that boxes that have to know everything
    are feeling the crunch of complex topology and instability;
    I don't see how Internet-II can get around this, and moreover,
    I do see how easily additional parallel infrastructure can worsen
    Problem A for everyone (and in particular for the Internet-II connectees).

    Also, have you noticed Vern Paxson and Van Jacobson saying that
    path symmetry really doesn't seem to matter with respect to 
    TCP throughput, or that path asymmetries even on point-to-point
    circuits has existed for some time in the real world?   I dunno,
    maybe very symmetric routing might help, but aren't you building
    some bad failure modes by trying to force this by building a star?
#2: Are you planning on building photon accelerators?

    BTW, what kind of delay do you get between Stanford and UCSD if
    you have a star topology?   You can assume that your physical
    topology is built out of the four principal right-of-way carriers'
    fabric, whether leased or otherwise.

#3: What type of per-packet and per-flow time budgets do you think
    you have at OC12 and OC48?   If you can make all this happen
    with existing technology (or can make new technology), then there
    are at least four companies that will want your resume ASAP, particularly
    if you can do this and accomplish your #2 (assuming you accidentally
    missed a digit) simultaneously.

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