Want to be able to access your machine anytime, anywhere? Can’t be bothered purchasing a domain name and configuring Dynamic DNS? Microsoft has a solution: the "Windows Internet Computer Name" -- a unique domain name for your computer.

There is one small catch though: you have to be using the next-generation networking protocol IPv6 which, although thoroughly integrated into Windows Vista, isn't supported by most home routers yet.

The Windows Internet Computer Name is an advancement on the Peer Name Resolution Protocol (PNRP), which is a name registration and resolution protocol initially developed for Windows XP.

Unlike traditional DNS, where domain name servers are used essentially to store a list of domain names and their corresponding numeric IP addresses, PNRP does all the domain name resolution peer-to-peer. Put another way, users of Windows Vista provide PNRP domain name resolution services for other Windows Vista users.

If you are still trying to wrap your head around how exactly this can work efficiently, rest assured you're not alone. However, a Wikipedia article on the topic makes it sound suitably clever (speed of the system is 'logarithmic to the size of the cloud', for example.)

On a basic level, here's how PNRP works: your PC has an IPv6 address -- a much longer string of numbers than the typical xxx.xxx.xxx.xxx IPv4 address. IPv6 addresses are, by design, accessible to everyone on the public internet, because there's a practically unlimited number of them available (unlike IPv4). You specify a name for your PC, and PNRP makes that available to other PCs on the internet, allowing them to connect directly to you.

Yep, you're going to need a very solid firewall to ensure your PC is kept secure when running PNRP.

There’s a full run-down on PRNP on Microsoft TechNet – click here.

The product manager for PNRP at Microsoft, Noah Horton, has a good blog that explains more about it.