After years of dismissing the frantic pleas of standards bodies and industry groups to develop and implement an IPv6 transition plan, telecom and cable operators have begun to ready their networks to support the next-generation Internet protocol. Early adopters say carriers undergoing the transition need to realize that a successful IPv6 migration requires more than just upgraded router software.
"Most backbones I'm aware of have deployed IPv6 or plan to deploy IPv6 at some point," Junkins said. "I haven't seen a lot of resistance [recently]. People have accepted that it's something that has to be done."
This burst of activity isn't quite so surprising. The worldwide IPv4 address pool has been shrinking for the past decade and is expected to dry up in less than a year, according to John Curran, CEO of the American Registry for Internet Numbers (ARIN), who has been pressing carriers to move faster on their IPv6 migrations.
"For some carriers, this has reached the level of the boardroom and is something first and foremost they're paying attention to. For others, it seems to be something that is a distraction," said Curran, former CTO for XO Communications. "IPv6 is the answer [the Internet Engineering Task Force (IETF)] came up with. People who say they're sure something else will come along don't realize IPv6 is what we came up with 15 years ago."
Completing an IPv4 to IPv6 migration is a massive undertaking for carriers, and many have been reluctant to take their top engineers off more lucrative projects to tackle what executives see as unprofitable housekeeping, Curran said.
"For a lot of people, it seems like a task that has no reward," he said. "[Carriers] are worried about how they're going to get business done -- that new application upgraded, that new service rolled out to customers. Something that's needed in a year and doesn't have any immediate benefit is going to get cut out of everyone's budget."
IPv6 transition plan must consider core, access and back-end systems
Comcast began its IPv6 transition plan five years ago, according to John Jason Brzozowski, distinguished engineer and chief architect of the IPv6 program at Comcast Corp.
"When you plan ahead and you have more time than not, it allows you to do things in smaller increments," Brzozowski said. "The more you change in one shot, the more opportunity you have for error. So, one of the things that we've done is spread a lot of this work out over an extended period of time in small increments, which is something we can really [credit for] helping alleviate the impact [on subscribers]."
An IPv6 transition begins with ensuring that core network infrastructure -- hardware and software -- has the ability to support the new 128-bit hexadecimal addressing specification, he said. From there, carriers must address network design and architecture considerations, such as how to handle Border Gateway Protocol (BGP) and Interior Gateway Protocol (IGP) over IPv6.
Access network needs vary based on the provider, Brzozowski said. For Comcast's implementation, engineers are collaborating with nonprofit industry groups such as CableLabs to understand the best way to enable IPv6 over its access layer technology, Data Over Cable Service Interface Specification (DOCSIS).
Carriers must also ensure IPv6 support for advanced services, such as domain name system (DNS) services, according to Matt Sewell, Global Crossing's director of product management for Internet services.
"Making sure those applications can support IPv6 is just as important, if not more so, than the network itself," Sewell said. "The network is, in some ways, the easy part."
Support for IPv6 must also extend to the often-overlooked back-end systems, such as homegrown and commercial operational support systems (OSS). Many operators struggle with integrating OSS into their IPv6 transition plans. They will have to rewrite or upgrade a help-desk application whose fields aren't sized for a router's 40-character IPv6 address, Curran said.
"You run into the problems with the things you built yourself," he said. "It's not your equipment that's the problem. It's the tools and infrastructure you privately developed."
Although NTT America uses some commercial router configuration tools that are IPv4-capable only, running a dual-stack environment means engineers can continue to monitor them via their IPv4 addresses, Junkins said. NTT has redesigned tools that were developed in-house to support IPv6, he added.
"In our case, those were tools we'd written ourselves, so as we evolved over time, we saw the need for it very early," Junkins said. "We were able to include IPv6 in the design of those tools as we developed them over time."
Brzozowski said Comcast's conservative timeline for IPv6 enablement has ensured that all relevant back-end systems can accommodate the new IP address fields.
"We basically took the time to make sure that we inventoried and assessed all of these systems so that we could gradually introduce the functionality required to support IPv6," he said. "A lot of people believe that you should 'just turn it on,' … [and] while the message we send is [that] this is all doable, this is all achievable and we're evidence of that, it requires planning."
Let us know what you think about the story; email: Jessica Scarpati, News Writer