The Choice: IPv4 Exhaustion or Transition to IPv6

Iljitsch van Beijnum iljitsch at
Thu Jun 28 22:20:14 UTC 2007

On 28-jun-2007, at 19:56, Dave Israel wrote:

>> You don't believe the killer app will be "sorry, no more IP  
>> addresses?"

> I bet it won't.  There are too many people willing to patch what we  
> have rather than toss it out and start over.  As the IP addresses  
> run ever lower, ISPs will probably patrol usage even more and  
> reclaim IPs.

The Comcasts of this world burn addresses by the millions. If they  
can't have new ones for (almost) free, they'll have to stick multiple  
customers behind a single IPv4 address. If you have to share your IP  
address with several of your neighbors, it becomes attractive to add  
IPv6 to the mix to make peer to peer stuff, including VoIP, work more  
reliably. QED.

> Then router vendors will probably propose new routing schemes that  
> don't require bit boundaries, so allocations can be made outside  
> the powers of two, and ISPs will reclaim more and reallocate it.   
> The routing tables will get bigger, but since memory is getting  
> cheaper, we can work around that, too.

It will sure be interesting to see who attempts to and who succeeds  
at breaking through the /24 barrier.

> customers are not going to give a rodent's behind about IPv6.

True, but they don't care about IPv4, either. They just want to talk  
to Youtube and Myspace. Whether that happens over IPv4, IPv6, CLNP or  
avian carriers doesn't matter.

Guess what. I turned off IPv4 for half a day a while back. I couldn't  
print and instant messaging was a problem, but other than that, with  
a dual stack proxy to take care of the difference, it worked pretty  

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