I was asked this week: "What is IPv6 and what do I have to do to my PC now to support it?"

So first, what is it?

In the simplest terms, Internet Protocol version 4 an 6 (IPv4 and IPv6) are the Internet network standards that are and will be used (resp) by any device connected to the Internet. IPv4 is the Internet Protocol that is currently used, and IPv6 is the next generation. You might've seen articles proclaiming that we're running out of available addresses -- this from Forbes, "Is The Internet Out Of Room"? (4/11/2006):

"The Internet is supposed to be limitless--a boundary-free exchange of digital information and profit. So how can it be running out of real estate?

"The answer, according to information technology experts, lies in cyberspace's ever-growing popularity. In theory, each new user who wants to log on needs a new address, as does each new Internet-enabled gadget, like smartphones that can access the Web. Routers, which allow multiple users and devices to use a single address, are helping stave off the problem for now, but it's only a stopgap measure."

Moving to IPv6 will increase the available addresses, just as adding digits to phone numbers increases the possible number of phones you can support. In the case of Internet-connected devices, this means that we will move from a system with a limited number of addresses today to an almost unlimited number. BusinessWeek has an article in print and online this week that looks at this worldwide network upgrade that provides "an almost limitless number of addresses."

IPv4 vs. IPv6

"The problem -- all the possible Net addresses will be used up in five years -- can be solved by upgrading the decades-old standards that govern how different devices communicate with each other. The upgrade, called Internet Protocol version 6, was developed a decade ago and mostly has been sitting on the shelf -- until now, that is. Anxious about how China and Asia are starting to upgrade their computer systems to take advantage of IPv6 capabilities, the Defense Dept. and the White House are trying to jump-start IPv6 use in the U.S. through billions of dollars in technology improvements... Says Charles Rossotti, a senior adviser to private-equity firm The Carlyle Group... "Some significant sectors of the economy, notably the Defense Dept., are starting to move quickly."

"Or at least as quickly as a bureaucratic behemoth can move. Even simple shifts in organizations as complex as the Defense Dept. are difficult. Although the government plans to spend tens of billions over the next 10 years to upgrade its computer and phone systems, it faces competition for that funding from the Iraq war."

Chris Harding, an IPv6 Forum Fellow, says that "it is not a matter of whether, but of when, IPv4 addresses will run out. Commercial users will increasingly demand guaranteed levels of service, (and) without improved and selectable quality, some services will not be feasible."

Adding more IP addresses will allow every device to have their own, unique IP address on the network: according to the wiki, IPv4 supports 4.3 billion addresses, which won't cover everyone and their mobile phone, TV, PC and Internet toaster. In contrast, IPv6 virtually supports an unlimited number of addresses, with about 50 octillion for everyone on the Earth today. That's enough for everyone in our home, where we are barely into using two digits worth of IP addresses... including business use.

So what do you have to do?

Realistically, no new changes for consumers. Today, current schemes to re-use IP addresses dynamically works fine for e-mail and surfing the Internet, so you may not need to worry about setting up anything new on your PC our router at home. In most cases, your Internet Service Provider (ISP) will handle the heavy litfing. Many major businesses, ISPs, CE companies, network equipment manufacturers and governments are making changes already, or should be mapping out their plans.

Microsoft supports IPv6 in Windows Server 2003, Windows XP SP1 and SP2, and Windows CE .NET 4.1. Windows Vista and Windows Server "Longhorn" include the Next Generation TCP/IP which supports IPv4 and IPv6 . If you want to make the move today with current products, TechNet has more details in the IPv6 FAQ, available online, including details on installing the IPv6 protocol for Windows XP and Windows Server 2003.

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