We need it soon. The supply of Internet Protocol version 4 (IPv4) addresses is dwindling, spurring interest in the transition to IPv6, with its exponentially larger address space. Since the IPv6 standard was established in 1999, operating systems and network equipment have steadily added support, says John Curran, president and CEO of the American Registry for Internet Numbers. But the transition got started so early that it has since faded into the background.\n \n It's no cause for panic. \u201cAs we got into the mid-2000s, people started thinking, \u2018Maybe we don\u2019t need it, maybe this is a false alarm,\u2019\u201d says Curran. But addresses are running out faster than ever, consumed by things like \u00adsmartphones. Even if your organization has all the IPv4 addresses it needs, it will soon have to coexist with a many more IPv6 users elsewhere.\n \n It\u2019s not sexy. The main virtue of IPv6 is its 128-bit address space, compared with 32 bits for IPv4. Unfortunately, those aren\u2019t the kind of numbers that get CEOs and CFOs excited. Outside of the U.S. Department of Defense, which is attracted to the encryption in IPv6, most CIOs will have a hard time making a business case for the switch. \u201cWhen everybody\u2019s forced to do it, that\u2019s when the rubber is going to hit the road,\u201d says Frank Troy, an IPv6 consultant.\n \n Websites need to learn it. As users move to IPv6, your server won\u2019t know how to talk to them if it\u2019s still on IPv4. Google provides a separate subdomain for early adopters (ipv6.google.com). IPv6 network managers who want users to have access to www.google.com must make special arrangements. Google has held off on advertising an IPv6 address for its primary domain because only 0.1% of visitors need support for a dual v4\/v6 configuration.\n \n Workarounds may be imperfect. Internet service providers will compensate for the differing protocols by creating gateways to relay traffic between nodes that can\u2019t talk directly, but that could hurt multimedia performance or interfere with location-based services, Curran says. If those things are important to you, you need to add IPv6 support\u2014at least to your Web servers and firewall.