Internet protocol version 6 will give every computer, cell phone and radio frequency identification tag its own unique address on the Internet, opening up vast potential for new types of communication and innovation. But getting there isn\u2019t free.IPv6 is the nine-digit ZIP code of the Internet: It vastly expands the potential to pinpoint communications on the Internet. Every device\u2014from cell phones to refrigerators to bullets\u2014will have its own address, which means engineers can build a multitude of new applications and services for this greatly expanded and constantly connected network. But the good-enough nature of today\u2019s Internet and the cost of moving to IPv6 could mean that adoption is as halfhearted as it was for those longer ZIP codes. Here are the major benefits and costs: BenefitsUbiquitous connectivity. Every device on the Internet gets its own IP address and can be constantly connected\u2014without requiring human intervention. This will spur the development of new applications and services that take advantage of the new capabilities.Reduced network administration. Since every device on an IPv6 network can connect directly to the Internet, there is no need to set up and maintain internal networks. And since IPv6 devices can come online themselves, configuration becomes much easier. The Department of Commerce estimates that network management costs will drop 30 percent thanks to IPv6.Improved security. Longer IP addresses mean that each device has a unique identifier. This will allow for device and user-level authentication\u2014meaning spammers and hackers can\u2019t hide behind constantly shifting IP addresses, as they do today. The security paradigm will have to change from firewall-centric to application-centric, but once it does the Internet will be a much safer place.More efficient. IPv6 is designed so that the first packet in a stream of data has all the header information for the entire cluster. The result is that IPv6 transmission takes up less bandwidth than IPv4 transmissions.CostsEquipment replacement. Over time, CIOs will need to replace all their IP-enabled devices, including routers and switches, printers and PCs, with IPv6-compatible equipment. If they do it as part of the normal hardware refresh cycle then the extra cost will be negligible. If they wait until there\u2019s a need to make a sudden, wholesale swap-out, the new hardware alone could amount to a onetime multimillion-dollar hit for large companies.Application rewrites. Applications will need to be rewritten for IPv6 users. It is unclear how costly this will be\u2014it depends on the application. But do not buy a package or upgrade to a new version without first finding out what your vendor\u2019s IPv6 transition plan is. Retraining. Network administrators will need to be trained in the new environment: A full-time IPv6 network specialist will cost around $165,000 a year, according to Department of Commerce estimates.