The Internet is likely to run out of IPv4 address spaces by early nextyear, Richard Jimmerson, CIO of ARIN, the American Registry forInternet Numbers, warned his audience during a speech Wednesday at LISA, the 24thLarge Installation System Administration Conference, being held in SanJose, Calif., through Friday.
“By the end of the first quarter next year, the IANA free pool of IPv4addresses will deplete,” Jimmerson said.
IANA, the Internet Assigned Numbers Authority allocates and maintainsdomain names, coordinates the global pool of IP addresses and managesthe numbering systems of Internet protocols, among other things.
Where Have All the Addresses Gone?
The IANA has only 12 blocks of /8s left. A /8, pronounced “slasheight,” is a block of approximately 16 million unassigned IPv4 addresses. [*Correction – Dec. 2, 2010] IANA dolesout one or two /8s at a time to regional Internet registries (RIRs)such as ARIN on request.
An RIR manages the allocation and registration of Internet numberresources within a particular region of the world. ARIN is one of fiveRIRs, and its area of coverage is North America and parts of theCaribbean.
Although 12 /8s seems like a lot of IPv4 addresses, they can go veryquickly. Once the IANA has five remaining /8s left, it will allocateone to each of the RIRs, at which point each RIR will hold between oneand three /8s.
That’s up to 192 million IPv4 addresses for each RIR, enough toprovide about two-thirds the population of the United States with oneaddress each So why the fuss?
“There may be a lot of pent-up demand out there for IPv4 addressesfrom large organizations that are working their way through theprocess,” Jimmerson explained. “If the top 10 providers within the U.S.and Canada came in at one time and all ARIN had left was one /8, theycould deplete it within one day.”
Scrambling for the Crumbs
There are lots of underutilized blocks of IPv4 addresses that havealready been allocated, and ARIN is trying to reclaim them, sometimessuccessfully.
“We just received a /8 block at ARIN last month,” Jimmerson said. “Butdo not allow the fact that you see us getting these back to convinceyou that we won’t run out. Getting an entire /8 back extends the lifeof IPv4 by a few weeks.”
LTE 4G services that are rolling out worldwide are going to be anotherdrain on IPv4 addresses, Jimmerson said. “Some of the service providerswill use IPv6 to provide that service and others will use IPv4, andthere’s nothing we can do to prevent them from using IPv4. If theyrequested more IPv4 addresses because they’re rolling out a newservice, we’ll issue the addresses to them.”
*ECT News Network editor’s note – Dec. 2, 2010: Our original published version of this article states that a /8 is a block of 64 million unassigned IPv4 addresses. In fact, a /8 holds approximately 16 million IP addresses.