The Last Five IPv4 “Slash Eights” (/8s)
The IANA IPv4 registry has been updated to reflect the allocation
of two IPv4 /8 blocks to APNIC in January 2011: 39/8 and 106/8.
You can find the IANA IPv4 registry at:
Please update your filters as appropriate.
Only five unallocated unicast IPv4 /8s remain.
Number Resources Manager, IANA
What does this mean?
- Only five /8 remain in the IANA free pool.
- Those five /8 are technically reserved; one for each RIR.
- We can now consider the IANA remaining IPv4 pool empty.
- Therefor, with this request, we have entered into the “exhaustion phase.”
- IANA must now “Proceed to allocate one /8 to each RIR from the reserved space.”
In other words, the IANA is effectively out of unreserved unicast IPv4 addresses. Since they did not announce the allocation of the “last five” today along with the allocation to APNIC, we can likely assume that they will make that announcement/allocation at a date of their choosing. How long they can wait is an open question for me. They are required to proceed but are not specifically limited to any explicit timeline… My guess is that they will not drag their feet and that we will see this announced later this week.[EDIT: I just got word from a very reputable source that “There is an event scheduled for later this week in Miami. Details forthcoming tomorrow.” You’ll hear as soon as I do!]
FYI, the remaining five slash eights are: 102/8, 103/8, 104/8, 179/8 and 185/8.[UPDATE (3-FEB): The IANA IPv4 Address Space Registry is now fully allocated:
102/8 AfriNIC 2011-02 whois.afrinic.net ALLOCATED
103/8 APNIC 2011-02 whois.apnic.net ALLOCATED
104/8 ARIN 2011-02 whois.arin.net ALLOCATED
179/8 LACNIC 2011-02 whois.lacnic.net ALLOCATED
185/8 RIPE NCC 2011-02 whois.ripe.net ALLOCATED
It was announced this morning, as expected. Goodbye IPv4!]
What this does not mean:
- The Internet will not explode, implode or otherwise cease to function.
- IPv4 addresses will not cease to work.
- IPv4 addresses are not quite all gone; organizations can still get free IPv4 addresses from their RIR (it’s the global pool that is exhausted).
- We wait for IANA to announce the allocation of the last five /8 to the five RIRs. (3 February, 2011)
- The RIRs continue to hand out IPv4 addresses according to their policies, until they each exhaust their own supplies.
- IPv4 addresses become more expensive as they become harder to get.
- Due to this expense and scarcity; many ISPs deploy some form of NAT and likely implement various forms of IPv4 address rationing. Various breakage ensues.
- Networks continue to deploy IPv6, without the NAT related breakage now found on IPv4.
- Over the coming years; IPv6 takes over as the dominant protocol on the Internet.
In short; if you have not looked into IPv6 yet, start! If you have, accelerate! The faster you are fully IPv6 enabled, the less pain you (and everyone you connect to) will be required to feel during this transition.
Want more info?
- ARIN has already put up an “IPv4 IANA Free Pool Depletion – FAQ” with more info.
- Find more about IPv6 on The IPv6 Experts .net or contact one of The Experts listed there.
- You can contact me directly for interviews, consultation and more: chris <at> chrisgrundemann <dot> com.
- Or, you can just leave a comment with your question(s) here!