IPv6: Leave It To Service Providers

As the world begins a transition from IPv4 to the new Internet protocol, IPv6, users will rely on service providers – and they have had a demonstration of what an IPv6 Internet service looks like today, in Paris.

The world supply of IPv4 addresses has now been handed out to regional registries, and will gradually be given out to ISPs and other customers, after which users will all have to use NAT (network address translation), slowing the Internet and losing its end-to-end virtues, or else move to the new IPv6 protocol with its larger address space.

The case for moving to IPv6 will be put at the V6 World Congress, in Paris until Friday, and delegates will be using an IPv6 wide area service provided by Colt and delivered to the Marriott Rive Gauche conference centre by Colt’s customer, an ISP specialising in hotel services, called iBahn.

Colt and iBahn say this is their first full IPv6 service: “iBahn has worked closely with Colt to enable the first production IPv6 line that either company has installed,” said iBahn’s chief technology officer Tom Duke in a statement.

eWEEK Europe spoke to Colt’s director of network architecture, Nicolas Fischbach, to find how organisations should approach the move to IPv6.

2011 is the year of IPv6

The issue of IPv4 depletion has received a lot of media attention in the last few weeks, and Fischbach believes 2011 is the year to start moving. But he repeated the industry’s message that there is no need to panic, and presented IPv6 transition as an issue where big carriers can make the difference.

“The V6 event is the first one of its size that is dedicated to V6 and, to be honest, I think it’s the right point in time,” said Fischbach. “Last year it would probably have been too early, next year would be probably too late. I think the good thing is there are a lot of people already turning up and presenting, and sharing their experiences. It will help shape the perception, tone down the panic, explain the value to the enterprise, the service provider, the consumer – what this is really about.”

According to Fischbach, the main challenge for the industry will not be the implementation of IPv6, but managing the “brokenness” that is likely to occur when organisations begin their migration to to the new addressing system.

“We’re running dual stack in the network. IPv4 is going to be here for a long time, so if someone says IPv4 is going to disappear in the next five years, they’re wrong,” he said. “We will probably still have part of the network being IPv4-enabled fifteen to twenty years from now. And the big challenge on the network side is really the maintenance, because both IPv4 and IPv6 have to coexist.”

Carrier-grade NAT

Fischbach explained that some parts of the network will be duplicated in order to manage the change, and carrier-grade NAT (network address translation) will also appear in the network, to help bridge the gap between IPv4 and IPv6. “People actually hate it because the amount of complexity this is going to introduce to the networks,” he said.

Carrier-grade NAT is an approach to IPv4 network design where end sites are not given public IPv4 addresses. They are instead given private addresses that are translated to public by middleboxes embedded in the network operator’s network. This allows the network operator to share one public address among several end sites.

However, critics claim that this breaks the end-to-end principle of the Internet and has significant security, scalability and reliability problems.

“We know that if you start to fiddle with the customer traffic at the application level you’re going to break it at some point. And that’s why most service providers push back on carrier-grade NAT,” said Fischbach. “We will have to do it at some point, because of the coexistence of IPv4 and IPv6, but how to manage this probably will be a question for most of us in the industry.”

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