IPv6 Addressing Help

Nathan Ward nanog at daork.net
Sat Aug 15 02:03:05 CDT 2009

On 15/08/2009, at 4:34 PM, Randy Bush wrote:

>> I'm going to contradict you there. Classful addressing had a lot to
>> recommend it. The basic problem we ran in to was that there weren't
>> enough B's for everyone who needed more than a C and there weren't
>> enough A's period. So we started handing out groups of disaggregate
>> C's and that path led to the swamp.
> the swamp preceeded cidr
> and, if you had a bit of simple arithmetic clue, you would realize  
> that,
> unless you are prescient, you will always run out of some classes  
> before
> others.  as we are very poor at predicting the future, there was no  
> win
> to be had in classful.

This is really this basis of my reply, so, I'll just say +1

Read about how sparse allocation/binary chop stuff works. You get the  
same amount of routes in your IGP table (or less) but it's much more  

Nathan Ward

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