The AC/DC lesson: Why IPv4 will be with us a long time

June's World IPv6 Launch Day was generally regarded a success. Several large content providers, Web destinations and carriers enabled the new Internet Protocols in their networks and millions of users were able to connect with no disruptions.

The IT world today faces a shortage of trained, experienced workers to manage Version 6 of the Internet Protocols. But if today’s IPv4 managers wait around long enough, they might find themselves in demand again.

The transition to IPv6 still has a long way to go, especially in this country.

Related coverage:

On World IPv6 Launch Day, governments in the cockpit

“I’m still trying to get people’s attention, particularly in the United States and Europe,” said Johannes Ullrich, chief research officer at the SANS Institute. The challenge today is not so much to get IPv6 implemented, but to do it correctly. “IPv6 is enabled in pretty much any operating system today, but it is hardly ever implemented in a structured fashion.”

The result of this uncontrolled deployment is shadow IPv6 networks running on top of managed IPv4 networks. This will change over time as IPv6 becomes the default technology for Internet growth, but legacy IPv4 is likely to remain with us long after IPv6 becomes the standard.

For how long is hard to say. But if history is any indication, it could be for a long time. The battle between direct and alternating current for dominance in the nation’s power grid -- the great technological revolution of a century ago -- offers an interesting parallel.

Electrification began with direct current systems. DC, much like IPv4, worked well enough at the time but had problems scaling. It was impractical at that time to distribute it over long distances, making large-scale networks impractical.

DC had a powerful advocate in Thomas Edison, but George Westinghouse and Nikola Tesla managed to demonstrate that alternating current was more effective. By the turn of the 20th century the battle had been decided. Growth of the grid continued with AC, and legacy DC systems eventually were transitioned.

Con Ed in Manhattan, where Edison had established a DC power station as early as 1882, began transitioning to AC in 1928. But it wasn’t until 70 years later that it began eliminating DC power. At that time the company still had 4,600 DC customers in Lower Manhattan, mostly in older buildings that used direct current for physical plant operations such as elevators. It wasn’t until 2007 that Con Ed finally ceased DC distribution, when the last customer was outfitted with its own power converter.

Direct current continues to be used today not only in battery-powered electrical devices, such as your laptop and smart phone, but also in subways and railways and even for bulk transmission from generators via high voltage DC.

The AC/DC current wars are not exactly analogous to the transition from IPv4 to IPv6, but they remind us that legacy technology tends to remain in place for as long as it works.

There is a shortage today of administrators with training and experience in managing IPv6, Ullrich said. “I think we’re behind the curve. One of the things we’re missing is operational experience.”

This will change as IPv6 is more widely adopted and administrators gain hands-on experience managing these systems. At some point -- and we don’t know yet when it will be -- the balance will tip and the shortage will be in experienced workers to manage and maintain legacy IPv4 networks.

No one will want to study the obsolete protocols, and like the Cobol programmers who periodically are called out of retirement in times of crisis, IPv4 old-timers are likely to find their skills in demand.


About the Author

William Jackson is a Maryland-based freelance writer.


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