I’ve been working with Phil Windley on key issues in digital identity and trust networks for a long time now, and particularly closely in the past year since Kynetx became one of the first Founding Partners of the Respect Network.
But rarely have I seen technologies that work so well together as KRL and XDI. Besides their uncanny synergy in personal cloud architecture, recently Phil has done two blog posts about PDOs (“persistent data objects”):
As I read each of these points, every place I see the term “PDO” I read “XDI graph”. XDI is a way to have universal interoperability and portability of PDOs. (This doesn’t mean that every PDO must use XDI, just that XDI is a way to have widely interoperable PDOs.)
That immediately explains the synergy between XDI and KRL: as a rules language and CloudOS, KRL provides a way to write programs to work with PDOs anywhere in the cloud, and XDI is a way to address, serialize, and exchange those PDOs.
If you start from a conventional object-oriented perspective (hmmm, I remember back when object orientation was the radical new perspective 😉 ), here’s another way to think about it: if XDI provides interoperable data abstraction, KRL provides interoperable method abstraction.
In other words, KRL provides a rules-based mechanism that enables a developer to apply a method (“action”) to any PDO that satisfies the necessary conditions (“event”) to fire that method.
No wonder KRL and XDI are digital chocolate and peanut butter.
Equals Drummond 
As we work on integrating XDI and KRL, I often have to think about one of my early computer science classes, which was called “Algorithms and Data Structures”. To a young student it might not be immediately obvious why algorithms and data structures would be covered in a single course, after all, aren’t they both vast and diverse areas? Yes, but you soon realize that they go hand in hand with each other, and that you can break down any problem in computer science into those two parts – algorithms and data structures. So, to me, a combined XDI/KRL architecture is nothing else than this old insight applied to the emerging world of Personal Clouds. You want both parts, and you want them to work together seamlessly. Then what you get is a foundation on which you can solve any problem.
A huge +1, Markus. Right on.
As we work on integrating XDI and KRL, I often have to think about one of my early computer science classes, which was called “Algorithms and Data Structures”. To a young student it might not be immediately obvious why algorithms and data structures would be covered in a single course, after all, aren’t they both vast and diverse areas? Yes, but you soon realize that they go hand in hand with each other, and that you can break down any problem in computer science into those two parts – algorithms and data structures. So, to me, a combined XDI/KRL architecture is nothing else than this old insight applied to the emerging world of Personal Clouds. You want both parts, and you want them to work together seamlessly. Then what you get is a foundation on which you can solve any problem. 🙂
Markus, I’m not sure why this comment appeared twice, but no matter, it’s worth reading twice 😉