estimation of number of DFZ IPv4 routes at peak in the future

Owen DeLong owen at
Tue Mar 8 22:40:51 CST 2011

You have ignored the probability of disaggregation due to IP trading markets, especially
given the wild-west nature of the APNIC transfer policy.

Many of the legacy blocks will get dramatically disaggregated in the likely market which
could take the DFZ well beyond 500k routes.

It will be very interesting to watch.


On Mar 8, 2011, at 7:17 PM, Mikael Abrahamsson wrote:

> Hi.
> We had an interesting discussion the other day at work. We were speculating on how many DFZ IPv4 routes there would be at peak in the future before it starts to decline again due to less IPv4 usage. The current number is around 350k, and my personal estimation is that it would grow by at least 100k more due to the the last 5 /8s being carved up at around /22 meaning each /8 ending up with 16k routes, plus the last allocations being seen in the remaining RIR "normal allocations" would be smaller than before plus de-aggregation of space as people "sell" or "lease" subspace of their allocations.
> My guess therefore is a peak around 450-500k IPv4 DFZ routes and that this would happen in around 3-5 years. I wanted to record this for posterity.
> What is your guess, any why?
> -- 
> Mikael Abrahamsson    email: swmike at

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