Akamai says one of its key engineering projects for 2010 is revamping its massively distributed network infrastructure to support IPv6, the long anticipated upgrade to the Internet's main communications protocol.

However, Akamai says its IPv6 software development and testing project is proving more difficult and taking longer than IPv6 efforts touted by Google and smaller content delivery network (CDN) rivals such as Limelight Networks due to the complexity of the algorithms and homegrown software that it uses to distribute Internet content close to end users.

"We're not just racking and stacking standard Cisco boxes and operating systems and making some tweaks to some applications to have IPv4 and IPv6," explains John Summers, a senior product line director for Akamai who is managing the company's IPv6 development effort.

"What we do in our mapping infrastructure is to build a performance map of the Internet. A lot of what we do for our content provider customers is provide superior performance by providing route optimisation across the fabric of the 12,000 service providers that are the Internet. Those mapping algorithms are pretty complex. Extending those mapping algorithms to the IPv6 space is difficult. As IPv6 rolls out, it's going to roll out in pockets, and that's going to make the routing around congestion points that much more important but also that much harder," Summers adds. "What we're solving is a much more complex problem" than Google's.

Akamai says it will complete its IPv6-related engineering effort later this year, and that it will begin a beta programme, dubbed a technology preview, for select customers by the first quarter of 2011. Akamai plans to have commercial IPv6 service available to all of its customers in the second half of 2011.

"IPv6 is going to be a problem for our large content customers in the back half of 2011. We need to have the core delivery service available in that timeline," Summers says. He adds that the company is approaching IPv6 methodically and carefully because "what we do with IPv6 has to be every bit as bulletproof as what we've done in the IPv4 address space."

Akamai's IPv6 efforts are significant because the CDN carries such a large share of the Internet's content. With customers such as the NBA, Clear Channel and Fox Interactive, Akamai delivers 15% to 30% of the Internet's traffic at rates that reach more than 4 terabits/second. When Akamai enables IPv6 services, many of the Internet's most popular websites will be able to support IPv6, too.

Akamai's experience with the next-gen Internet protocol runs counter to that of Google, an IPv6 pioneer that has claimed that its IPv6 development effort was easy and inexpensive. Google has been supporting IPv6 on its search, news, docs, maps and other popular services since 2009, and it IPv6-enabled YouTube in February.

Akamai rival Limelight Networks, a CDN that focuses on video content, demonstrated end-to-end IPv6 services with partners Comcast and Netflix in June 2009. Akamai says its network is harder to upgrade to IPv6 than Limelight's because it is bigger and more decentralised.

"Limelight has a more centralised infrastructure," Summers says. "We've got 75,000 servers, 1,000 networks, 1,500 different locations. That's really distributed. What we have to solve from a mapping perspective when I've got a dozen or 20 locations is different than if I'm serving IPv6 content from two or three locations."