No more IP for you

Mark Blackman mark at
Wed Jan 20 11:01:04 GMT 2010

On 20/01/2010 10:54, Paul LeoNerd Evans wrote:

> A major problem with IPv4 "addressing" is that global IPv4 "addresses"
> have become simply names, not addresses. They do not give any information
> on where to send the traffic, simply who it is. You need a BGP router
> with a full route set to know where to send it. On our border routers
> at $company we're currently looking at 305,000 prefixes. Supposing an
> absolutely minimal implementation of, say, 5 bytes per prefix (4 address,
> pack prefix length and next hop ID in a single byte), that's still 15MB.
> More likely it'll take much more space than that.. possibly more than
> the, say, 64MB that smaller Cisco routing boxes come with. That's every
> internet-BGP-talking box in the world, has to have that table. And it
> grows all the time..

Indeed, I suspect the ever-enlarging global routing table and consequent 
hardware upgrades have done far more for Cisco's bottom line than IPv6 
so far.

- Mark

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