Seems simple enough. By raising from 32 to 128 the number of bits available to identify each device on the network, IP Version 6 will blast into the stratosphere the range of possible network addresses, blowing past the current standard, IPv4, which tops out at an uncomfortably cozy 4.3 billion. The implications for software are enormous, and probably beneficial, but the transition to IPv6 has agencies asking questions.With all the focus on upgrading network backbones to IPv6, what will happen to the actual applications that ride on those networks? Will they all still work smoothly?Numerous agencies and their contractors have set up test labs to look for answers. The news so far is good. According to Ray Williams, manager of network enterprise architecture at Northrop Grumman Information Technology, a systems integrator involved in IPv6 testing for the intelligence community, 'We haven't had any surprises.'Given the June 2008 deadline set by the Office of Management and Budget, the focus on networks is understandable, but not necessarily wise. 'That's a real misstep,' said Pat Arnold, chief technology officer for Microsoft Federal.'People are being heads-down and focused myopically on the network issue. The network is really important to get in place, but it's our opinion the applications really need to move first,' Arnold said.Several technologies designed to bring IPv6 to existing networks, including 'dual-stack' gateways and IPv4 tunneling, are catching on, according to several experts. 'These technologies allow organizations to experience IPv6,' Arnold said. 'At the end of the day, IPv6 means nothing unless we have application support for it.'In many cases, IT managers need do little more than upgrade to the latest, IPv6-capable versions of their network-aware applications. For desktop programs such as Microsoft Word, IPv6 is a nonissue. 'It's totally unaware of the network layer,' said Yurie Rich, director of IPv6 operations for Command Information Inc. of Herndon, Va., an application development and consulting company and vice chair of the North American IPv6 Task Force, an influential advocacy group.'Most modern applications are virtually IP-agnostic,' said Hal Pierson, research scientist at the Federal Aviation Administration, which maintains several IPv6 test beds.The agency is targeting its backbone to meet the June 2008 deadline imposed by OMB'a deadline that has little to do with applications, said FAA chief technology officer Mark Powell.'We're trying to just stay low-key on this and let the guys with the pagers who maintain the networks give us advice,' Powell said. 'We're taking the attitude that we're just changing the plumbing.'Normal technology refresh cycles should help bring hardware and operating systems along, and regular asset-management tools can spot trouble based on an application's age.To be even more proactive, experts say IT groups might try requesting IPv6-enabled programs from their vendors.'At the very least, all new software must be IPv6-compatible, which is to say applications should be able to send and receive packets to and from any and all IPv6 hosts,' said Peter Sherbin, a NAv6TF volunteer and product manager for the Canadian networking vendor Rogers Communications.Microsoft Corp. has aggressively incorporated IPv6 across its product lines, and it provides utilities that customers are using to find problem code in their applications'a process Microsoft also went through internally. 'We've had to clean up some legacy code,' Arnold said.Which version of Windows, for example, should you run? Arnold said that while Windows 2000, 2003 Server and XP came with a usable IPv6 stack, it couldn't handle printing and wasn't widely used.Native IPv6 will arrive in Windows Vista, due out for enterprises by year-end. A server version, code-named Longhorn, is expected the following year.Rich commended Microsoft's aggressive stance but noted 'excellent' support among Unix variants such as Linux, HP-UX, Solaris and AIX. 'All of the vendors have done a very good job of supporting IPv6 at the network stack,' Rich said. 'It's the development community that's kind of fallen down on the job.'The reality is that there's no simple formula for a smooth transition. Instead, say experts, agencies must set up IPv6 networks to test applications on a variety of operating systems for several weeks.'Things will be less likely to break, because you're only using one standard,' said Williams. Security features that now present roadblocks to applications, such as firewalls, he said, should work better.They'll likely encounter many of the same challenges they have with IPv4, especially assigning IP addresses and configuring Windows' Domain Name Server. So-called hardwired addresses are a common culprit in older software.Williams said one customer, whom he did not name, found applications to be the 'long pole in the tent' when testing IPv6 on multiple server OSes. The solution, he said, was virtualization software, which makes one OS look like another to applications and avoids painful OS migrations.What about in-house development? Programming tool vendors such as Microsoft and Sun Microsystems Inc. added IPv6 support several years ago, so newer applications should work. Agencies that haven't yet ported legacy applications written in C or COBOL, for example, can probably employ the usual method of compiling them on newer languages and observing the results.'IPv6 is a Layer 3 networking protocol which remains transparent to applications,' Sherbin said.'Nevertheless, programmers will always be better off if they understand IPv6 packet structure.'The real sea change should arrive in several years, when IPv6 is ubiquitous and developers learn to take advantage of seamless, cross-network communication and the predicted explosion in mobile devices.A soldier in Baghdad, for example, could view on a wireless personal digital assistant the same intelligence data as an analyst sitting in the Pentagon. Arnold says Vista has features that make it easier to set up peer-to-peer wireless networks.'That's the beauty of IPv6,' said Geof Lambert, another NAv6TF vice chair. 'It's all about mobility, it's all about security, and it's all about ubiquitousness.'Williams was at a conference in Los Angeles last spring where he listened to a NASA official describe how the space agency wants to IP-enable all its communication. 'I was floored,' he said. 'This was a monumental change. He used the example of a guy walking on the moon in a space suit talking back to the base station using voice over IP. And all the instrumentation, like his heartbeat monitoring, would be sent back over the same IP link.'In other words, the more devices that ride on the IP network, the more robust that network needs to be. The same holds true as the amount of data moving around increases.'Look at the upgrades they're doing at [the National Oceanic and Atmospheric Administration],' Williams said. 'They're looking 20 years out. Right now they're using four-kilometer resolution for their satellite imagery, and they're going to go to one-kilometer. And that's really more than four times the amount of data they want to push around. An agency like NOAA will be among the first to go to IPv6 because of what they're being asked to do.'Homeland security applications, notorious for their siloed, incompatible communication systems, could benefit the most, according to observers, who cited nationwide 911 initiatives to link first responders across jurisdictions.'IPv6's true potential is in the applications it enables,' Sherbin said, while adding they have yet to arrive. 'People are just learning how to leverage the potential, which is networking hundreds of millions of items and automating millions of processes. IPv6 allows automating all that can possibly be automated.'
We haven't had any surprises,' while testing software over IPv6.
'Ray Williams, Northrop Grumman IT
Rick Steele
Independent operators'Fallen down on the job''I was floored'David Essex is a freelance technology writer based in Antrim, N.H. GCN technology editor Brad Grimes contributed to this story.