Reprinted from TidBITS by permission; reuse governed by Creative Commons license BY-NC-ND 3.0. TidBITS has offered years of thoughtful commentary on Apple and Internet topics. For free email subscriptions and access to the entire TidBITS archive, visit http://www.tidbits.com/ Apple Restores IPv6 Support in Base Stations Glenn Fleishman IPv6 has returned to AirPort Utility by popular demand in a release shipped out today, a reversal of its removal in version 6.0. The next-generation addressing system for the Internet, which replaces the empty pool of familiar IPv4 numbers (of the pattern 192.168.0.1), is required for the Internet to continue functioning. ISPs, network hardware providers, content sites, search engines, and groups that form the backbone of the Internet's infrastructure policy groups are all agreed. The Internet Society (the folks behind the IETF and RFCs) even [1]drew a worldwide line in the sand on 6 June 2012, to not just test IPv6 in a widespread fashion as in previous years, but to keep everything active from that point on and continue to expand the use of that new addressing scheme for ordinary users ' who shouldn't have to sweat the details. IPv6 is necessary because IPv4 simply doesn't have enough addresses to encompass the many billions of devices of all kinds that require Internet access ' and that's just today. In the future, every mote of smart dust might need an IP address. While NAT (Network Address Translation) allowed IPv4 to limp along for years along with a number of other behind-the-scenes tricks, IPv6's vastly larger number of possible addresses (3.4 x 10^38) is the only real solution. It's been over a decade since IPv6 became standardized, and 2012 is the year in which it's finally hit the flashpoint for adoption: IPv4 addresses are essentially exhausted (trading is still going on) and IPv6 infrastructure is ready but needs real-world commitment to bring about full operational equality with IPv4. Even if things break a little, IPv6 has to be pushed forward. (The reason it's taken so long? There's no financial reward, only a cost, in switching. It's inevitable, but it has to come out of somebody's budget in every organization.) And then Apple went and dropped IPv6 support in the housecleaning that resulted in AirPort Utility 6.0. The initial release of the AirPort Utility iOS app never had it. While many of the removed features had an impact only on network administrators, very few of whom use Apple Wi-Fi gear any more, IPv6 has a broader impact. Apple built it into Mac OS X years ago, and it's been fully supported in iOS from the start. Removing IPv6 meant that broadband modems plugged into AirPort base stations couldn't hand off IPv6 information to the base station nor to other devices on the same network. That's a problem. (See '[2]AirPort Utility 6.0 Adds iCloud Support but Removes Many Features,' 1 February 2012, for more details about the iOS app and the 6.0 changes.) But IPv6 is back! On the heels of many WWDC announcements, including a quiet release of an overhauled form factor and updated hardware for the AirPort Express base station, Apple also released updated iOS and Mac OS X apps. The primary reason was to add support for simultaneous dual-band networking in the new Express, and as such Apple updated the [3]AirPort Utility for Lion to version 5.6.1, and brought the [4]Windows version up to the same release number. (A 5.5.x tree for Leopard and Snow Leopard wasn't updated at this writing, although it had a revision at the same time as the original 6.0 version was released.) All 5.x versions of AirPort Utility included IPv4 configuration, and 5.x versions continue to work with all released AirPort base stations starting with 2003 models. But the updated [5]AirPort Utility 6.1 for Lion (and a [6]revised iOS app) includes support for the new Express and an Internet Options button that's been added to the Internet view. The main Internet view now lets you enter IPv6-based DNS servers, necessary for resolving domain names to IPv6 addresses. [7][tn_AirPort-Utility-Adds-IPv6.jpg] The Internet Options dialog includes a Configure IPv6 pop-up menu that offers the choices Link-Local Only (use only on local network), Automatically (pick up via DHCP from the broadband connection, like an IPv4 address), or Manually, which requires specific address entry. [8][tn_AirPort-Utility-IPv6-Options.jpg] For all but Link-Local Only, you can select Native or Tunnel, which refers to how the IPv6 connection is made. A native connection provides IPv6 service to all devices on the network; a tunneled connection encapsulates IPv6 traffic at the router and wraps it up to carry across an IPv4 segment of the network to reach a fully native IPv6 backbone. That's a little technical, I know, but it might help you talk to your ISP or other service provider when trying to enable IPv6. IPv6 isn't the most exciting technology in the world. If you're not involved in Internet infrastructure or IT, it's like listening to sewer engineers talk about the kind of plastic used in outflow pipes and their diameters. IPv6 is a necessary part of making sure the Internet continues to work, and all your geegaws continue to be able to obtain routable addresses. The bits must flow! References 1. http://internetsociety.org/news/internet-society-number-resource-organization-and-regional-internet-registries-reinforce 2. http://tidbits.com/article/12760 3. https://support.apple.com/kb/DL1536 4. https://support.apple.com/kb/DL1547 5. https://support.apple.com/kb/DL1537 6. http://itunes.apple.com/us/app/airport-utility/id427276530?mt=8 7. http://tidbits.com/resources/2012-06/AirPort-Utility-Adds-IPv6.png 8. http://tidbits.com/resources/2012-06/AirPort-Utility-IPv6-Options.png .