It's Ars Tech's turn to bang the IPv4 exhaustion drum

Iljitsch van Beijnum iljitsch at
Wed Aug 20 03:54:26 CDT 2008

On 20 aug 2008, at 3:31, Randy Bush wrote:

> matsuzaki-san's preso, i think the copy he will present next week at  
> apops:


He (she?) says packets will ping-pong across the link if they are  
addressed to an address on the p2p subnet that isn't used. However,  
this is only true if there is no address resolution on the subnet,  
which would be the normal mode of operation with IPv4 on p2p links  
because those links don't have addresses and there is no ARP. With v6  
on the other hand, ND can work on all link types and PPP does  
negotiate an address of sorts.

So whether this actually happens on a true point-to-point link is open  
with IPv6, and if it's a point-to-point ethernet or similar link you  
only get some neighbor discovery traffic that goes nowhere, not an  
increase in actual traffic.

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