CIDR FAQ

Paul Traina pst at cisco.com
Wed Aug 16 15:55:59 UTC 1995


  From: peter at demon.net
  Subject: Re: CIDR FAQ
  > That's why we want to deploy CIDR.  So we're not caught in this
  > bind...
  
  That's back to the mainstream discussion now. I would hope we all
  realise that CIDR is a sticking plaster and not the ultimate solution
  to the possible problems in the future ? I am certainly of that mind,
  and I think that "the CIDR working group" and all of us out here
  should not become the "Cisco workaround comittee".

I don't understand why some folks continue to believe that CIDR is a
band-aid or a "Cisco workaround" or some other such rot.  That is an
utter falacy.

CIDR is the exponential growth in resource requirements workaround
comittee.  It doesn't matter if you're using a PC, a pair of tin cans,
or a router,  if the number of routes required to maintain connectivity
doubles every 6 months, the cost of business for operating on the internet
will be prohibitive for everyone except "the big players" you guys are
spending your time smacking around.

We would be more than happy to sell you a new box, or more certified memory
every few months...hell, that sort of stupidity in the marketplace would
give us more than enough business justification for high-priority projects.

When CIDR was dreamed up,  there were two problems it was trying to solve,
routing and addressing.  If you don't do heirarchical addressing at some
places along your heirarchy,  then you need to deal with the fact that

    (a) everyone has all routes
    (b) everyone is ANNOUNCING all routes
    (c) when a route flaps, it affects everyone

  If you router is non-expandable then bitch to your supplier, be they
  Cisco, Bay, the-guy-down-the-road-in-the-garage - anyone.

I rarely see products that are capable of standing more than one or two
doublings in CPU and memory capacity.  They usually don't sell when they
are produced because their initial investment cost is 3x the competition.

  BTW - I have not studied the RFC's - so what will IPv6 do for us in
  the contect of routeing aggregation and latger boxes etc ?

It's a pity you haven't.  IPv6 makes the addressing problem much less of
an issue, but raised the number of routes in the internet from 2^32 to
2^128.  The only sane way to deal with this is aggregation, AGAIN.

So, the same pathetic fools who brought you CIDR are going to ruin your
IPv6 dreams before they've started.

I would ask that folks consider moving this OFF of the CIDR and NANOG
mailing lists and onto com-priv where it is much more "on-topic."

Paul



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