Where Chapter 1 described problems and shortcomings, this chapter gave hope about the existence of a sustainable solution.
We started by stressing the need for reaching a solution that would satisfy all online players. We went on exploring the current thinking about identity systems, showing how past errors and success stories were distilled through an industry-wide dialogue on the seven laws of identity. We introduced the Identity Metasystem, an abstract model that addresses the common issues of identity management in full respect of the identity laws. We have seen how the Identity Metasystem is not an alternative proposition to today's technology, but rather a further level of abstraction that relies on current systems and facilitates interoperability. Such a design choice guarantees investment protection and makes the solution future-proof, gracefully accommodating yet-to-be invented protocols.
We spent a fair amount of time on the WS-* specifications, understanding their role in the industry and digging into the details of the standards that are more relevant to the identity space. Once we gained more practical knowledge of web services, we were finally able to put all the pieces together and define a solid architecture for the Identity Metasystem model.
After the protocol aspects were all addressed, we defined the role of CardSpace as the user experience designed for empowering Windows users to be first-class citizens of the Identity Metasystem.
This chapter concludes Part I of the book, devoted to understanding the problem we are trying to solve, the solution in its entirety, and the intended role of CardSpace in the grand scheme of things. The remainder of the book focuses exclusively on CardSpace. What it is, how to use it, and how to design systems that take full advantage of it. Part II introduces the technology and the basic use cases from the user and developer viewpoints. Part III then goes into more depth about what it means to be an RP or an IP.