For IT professionals and network industry vendors alike, the events of last week represent a game changer regarding IPv6, which was developed in 1998 but has scarcely been deployed.
That change could be seen on Thursday when policymakers announced that the Internet has run out of addresses based on IPv4, after which companies from across the industry -- carriers, router manufacturers, makers of DNS, load balancing and other appliances -- issued a blitz of press releases and blog posts proclaiming their expertise in IPv6. (Details below.)
The cause of that flurry was clear: Pressure is building on network operators and content providers to upgrade their infrastructures to support IPv6 traffic ... sooner rather than later.
PANIC TIME QUIZ: How prepared are you for IPv6?
"It's not too late. It's not too late," urged John Brzozowski, Chief Architect for IPv6 and distinguished engineer at Comcast, the first U.S. carrier to begin trials of IPv6. "The sooner that folks get started, the more time they will have to tackle the problems they will face. In order to do this transition seamlessly and responsibly, you're best off getting started sooner."
"Because of depletion of IPv4, a lot of new users will only get IPv6 addresses. Once those IPv6 users get online, they are going to demand access to existing applications and services," says Qing Li, chief scientist with Blue Coat, which sells a range of network appliances that support IPv6. "During this IPv4 to IPv6 transition period, there are also going to be many, various security challenges."
Among the network industry leaders that made IPv6-related announcements last week were AT&T, Comcast, Juniper and Microsoft, while smaller players such as Blue Coat, Infoblox and Command Information touted their executives as IPv6 experts.
IPv4 address depletion
At a ceremony held in Miami, the Internet Assigned Numbers Authority (IANA) distributed the last blocks of IPv4 address space to each of the five Regional Internet Registries (RIR). Each registry -- including the American Registry for Internet Numbers (ARIN) in North America -- received what is called a /8 block of IPv4 addresses, which is around 16.7 million addresses, to dole out to carriers and other network operators in their regions.
Experts say it will take anywhere from three to seven months for the registries to distribute the remaining IPv4 addresses to carriers.
Once the registries hand out all of the IPv4 addresses, network operators and content providers must either deploy complex, expensive network address translation (NAT) technologies to share IPv4 addresses among multiple users, or adopt IPv6.
"This is one of the most important days of the Internet," said Rod Beckstrom, ICANN's President and CEO. "This marks the opportunity to shift to a version of IP that is so large it is difficult to even imagine ... and that can carry us into the future."
Experts say the deployment of IPv6 is necessary to allow the Internet to continue its unprecedented rate of growth. But it's going to be a costly, time-consuming exercise because IPv6 is not backwards-compatible with IPv4.
COMPARISON: IPv4 vs IPv6
IPv4 has run out of address space because it uses 32-bit addresses and can support only 4.3 billion devices connected directly to the Internet. IPv6, on the other hand, uses 128-bit addresses and supports a virtually unlimited number of devices -- 2 to the 128th power.
"The current IPv4-based network will, of course, continue to function as usual, but figure growth is constrained by the limited remaining availability of unused IPv4 addresses," said Leslie Daigle, chief Internet technology officer for the Internet Society, in a statement released Thursday.
While Daigle acknowledged that some early adopters have made their Web sites accessible to IPv6 traffic, more needs to be done. To help encourage IPv6 deployment, the Internet Society is hosting a 24-hour trial of IPv6 - dubbed World IPv6 Day - on June 8.
"We hope the milestone announced today sparks other organizations to plan for and deploy IPv6 as part of a strategy to ensure they are connected to a growing future Internet that is as dynamic and vibrant as todays," she added.
The Internet engineering community has been preparing for the inevitable depletion of IPv4 addresses for many years. In addition to the follow-on IPv6 standard, they've also created various translation and tunneling techniques designed to ease the transition from IPv4 to IPv6 and to allow the two protocols to co-exist in the future.
TRADEOFFS: IPv6 vs Carrier-Grade NAT
However, experts warned that network and Web site operators shouldn't rely on these stop-gap transition mechanisms for too long, recommending instead that they migrate to IPv6 as quickly as possible.
"In the long term, the application providers (and their clients) that use IPv4 addresses are likely to encounter issues because of the many kludges needed to keep those apps running," said Olaf Kolkmann, chairman of the Internet Architecture Board. "Meanwhile, applications that can communicate over IPv6-enabled networks will be more likely to encounter transparent end-to-end communication, enabling the continued development of innovative applications and services."
Kolkmann said it will be increasingly difficult - and expensive - for network operators to rely on NAT devices, application-level gateways and carrier-grade NATs to keep their IPv4-based networks up and running.
"With an IPv6-based Internet, endless possibilities lie ahead because every human on this planet, and their gadgets and devices, will be able to communicate, play, do business and supply services," Kolkmann added. "This explosive Internet growth can only continue with the larger address space that IPv6 offers."
The IPv6 sales pitch
The network industry responded to the news of IPv4 address depletion by hawking their wares to CIOs and encouraging them to move quickly to upgrade their network infrastructures to support IPv6.
Among the vendors that made IPv6-related announcements in conjunction with the IPv4 deployment news were:
* AT&T, which said it has enabled IPv6 for use with its VPN and managed Internet services for sites in the United States. AT&T said these services will be available to the majority of its global network footprint in 2011. AT&T also said it would enable IPv6 on other services such as remote access, hosting, managed premises equipment and VoIP throughout 2011.
* Comcast, which announced in a blog post that it was the first cable operator in the United States to provide its cable modem customers with a production-quality IPv6 service, activated 25 customers in Littleton, Colo. with what's called a dual-stack service, where IPv6 and IPv4 operate side-by-side.
* Juniper, which said it was speeding up its plans to support IPv6 on its public facing Web site. Juniper set up a special Web site that can handle IPv6 traffic immediately and said it was placing a higher priority on providing IPv6 access to its main Web site. Juniper also announced plans to participate in World IPv6 Day.
* Microsoft, which issued a blog post announcing that its Bing search engine would join in World IPv6 Day. Microsoft's key rival, Google, already accepts IPv6 traffic and is a key supporter of World IPv6 Day.
* A10 Networks, a load balancing equipment vendor, also announced plans to participate in World IPv6 Day.
Network vendors admit they see a big opportunity for sales in conjunction with the pending upgrade to IPv6.
The level of interest in IPv6 among CIOs "is shooting up like a rocket," Blue Coat's Li says. "The adoption curve is not a gentle slope. It's a straight line up. We're getting two or three calls a week from potential customers...including some of the largest service providers and enterprises in the United States."
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