More than 60 years ago, a group of scientists at the University of Chicago developed a symbolic clock face that could be used to graphically show just how close the human race was to midnight and catastrophic destruction and extinction.
The closest the hands of the Doomsday Clock ever came to midnight was in 1953, when the clock was manually set to two minutes before the final hour when the U.S. and the Soviet Union both tested nuclear devices within nine months of each other. The ominous symbol has since been reset nearly 20 times to reflect the ebb and flow of potential global calamity.
While Internet addressing is certainly not in the same crisis league as thermonuclear disaster, a number of experts believe that because of the address limitations of the current Internet Protocol Version 4 (IPv4), the Internet is running out of space and we are headed for catastrophe. The solution is to deploy IPv6, a next-generation protocol more than three decades in the making that uses an address bit size four times that of its predecessor and therefore provides a wider range of IP address possibilities.
The reality is that as servers get denser with blade and virtual computing, you have far more IP addresses per server, and you need to number them.
John Curran, Founder and CEO, The American Registry for Internet Numbers (ARIN)
At a networking conference held in Boston this year, for example, more than one speaker said the problem is reaching critical mass and we will run out of IPv4 addresses much sooner than expected. One expert claimed we are at DEFCON level, which is how the U.S. military classifies serious threats. Others maintained that developments like virtualization and cloud computing will exacerbate the problem as additional addresses crowd the Internet.
"The reality is that as servers get denser with blade and virtual computing, you have far more IP addresses per server, and you need to number them. You need to identify every server with a number, and as a result the usage is increasing," said John Curran, the founder and current president and CEO of the American Registry for Internet Numbers (ARIN) in Washington, D.C.
While the reliance on IPv4 and a shortage of Internet addressing won't have a direct impact on a data center or corporate WAN, it will affect access to a company's servers and Web facilities.
"There are going to be people connected to the Internet shortly with IPv6, and when they connect they won't be able to get to you," Curran noted. "Or they'll get to you and your Web server or email server through a gateway that has to convert their packets and millions of other people's packets and then won't be able to transfer email or use all the features of your website."
NAT goes to bat for IP addressing
Despite these predictions, many people are unconvinced that a reluctance to make the switch to IPv6 will create significant problems.
In fact, some analyst firms claim IPv6 adoption percentage rates in the commercial sector are in the low single digits.
"I'm not seeing a massive shift toward IPv6," said Tom Yohe, a member of the WAN Optimization Professionals group on LinkedIN. "Because most enterprises use network address translation (NAT) to change a small set of public IP addresses into a large set of private addresses, the urgency of moving from IPv4 is just not there."
Because IPv4 addresses are made up of 32-bit numbers, there are also more than four billion possible combinations, which would seem more than enough to support even the most robust growth of the Internet. Not so, say the experts, who predict exhaustion in less than two years at the current rate of consumption. One group has even constructed its own Doomsday Clock of sorts in the form of a downloadable IPv4 Exhaustion Counter widget that rapidly ticks off the estimated number of used addresses and days remaining until IP Armageddon.
"The piece that connects your company to every other company is IPv4 today and needs to become v4 and v6," ARIN's Curran said. "You need to get IPv6 on the public-facing side of your network."
Bringing IPv6 to task
This may not be as simple a task as it sounds. While IPv6 is basically an extension of IPv4 as explained by Silvia Hagen in her IPv6 tutorial, the newer addressing protocol defines a new packet format (128-bit vs. 32-bit) that is significantly different from that of IPv4, so the two protocols are reportedly not interoperable. Deploying IPv6 will also require some programming and engineering resources as well as a budget—things that are at a premium within most organizations because of the slow economy.
Until very recently, the people who sit on the decision-making side of businesses and oversee IT budgets also saw no motivating reason for approving the switch to IPv6. This attitude is changing, Curran noted, especially as threats of limited Internet access and services emerge as realities and corporate executives realize the possible impact on a company's competitive stance in the global market.
Ultimately, corporate "peer pressure" may be the tipping point for most companies to take the plunge into IPv6 waters. The federal government mandated that its agencies move their networks to IPv6 by June 2008 and issued the same stipulation to its suppliers.
In May, Orange Business Services flipped the switch on IPv6 in its IP VPN backbone, which provides managed communications and Internet services to 35 countries, reportedly becoming the first global service provider to do so.
Despite this progress and all the push-me pull-you arguments surrounding IPv6, most will agree that the move to a better addressing structure may just be a necessary first step on the long road to helping the Internet keep pace with technology developments and user demands.
"While v6 solves running out of numbers," Curran said, "it doesn't necessarily solve all of the Internet's architectural issues that we're going to see over the next 50 years."