This month, the American Registry for Internet Numbers (ARIN) announced that there are no more “large” IPv4 address blocks available to assign to North American organizations that need them.  Today, ARIN has available fewer than 275 of the smallest block size (a /24, or 256 IPv4 addresses).

It’s time for stragglers to adopt IPv6, which provides a virtually infinite number of IP addresses.

(1) IPv6 is Roomier:  IPv4 32-bit addresses allow for 2^32 or about 4 billion unique addresses; there are now more cell phones than that, and Earth’s population now exceeds 7 billion people.

IPv6’s 128-bit addresses allow for 2^128 or about 340 billion billion billion billion unique addresses.*

(2) IPv6 is Cheaper: While the cost to acquire new IPv4 address blocks spikes, IPv6 address blocks are available for free.  “IPv6 address space is effectively free and infinite, yet more and more organizations are apparently now paying large sums to continue to acquire IPv4 addresses.”

(3) IPv6 is Faster:  (a) “Facebook says it has seen users’ News Feeds loading 20% to 40% faster on mobile devices using IPv6.”

(b) In a 2015 presentation at RIPE-70, “Latency IPv4 vs IPv6: Understanding the difference,” Alexander Azimov reported first that IPv6 traffic noted that studies in 2010 and 2012 found that IPv6 traffic is faster than IPv4 traffic.  His research found that although IPv6 routing options appear to be more limited than IPv4 options, in fact IPv6 traffic actually appears to access 45% more possible paths than IPv6 traffic.  Video: … PDF:



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