Joe McKendrick kicks off a thread on the current state of SOA Security. As usual, most discussion of SOA Security applies to "how SOA can be made secure". This is understandable. And, as some commentators have pointed out, there is a body of Best Practice out there on how to secure services in an SOA. For example, Randy Heffner provides lots of good advice on how to secure the services in an SOA)

But, there has been relatively little debate on the flipside of SOA Security - how SOA can apply to security.

Because, really, "SOA Security" is two separate things, solving two separate problems. The first, most obvious thing, is that it applies security to SOA. The problem it is solving here is "SOA is insecure". Randy Heffner's advice is good here: there are products and procedures for applying security to SOA. But, "SOA Security" also has the meaning of "applying SOA principles to security". i.e. "SOA-flavored security", if you like. The problem which is being solved there is the difficulty of deploying security. Joe McKendrick hints at this in his comment here

: "Could security services be delivered through the SOA infrastructure, and provide an enterprise-level solution, versus application or system-level approaches?"

"SOA-flavored Security" means making security more manageable and easy to deploy by isolating re-usable components of security and providing them as managed services. For example, the OASIS DSS standard explains how digital signature services can be used in order to provide signing and signature validation services over the network, accessed using a Web Services interface. This solves a knotty problem, and provides a good framework for key management. Similarly, specifications such as XKMS, XACML, and WS-Trust are really all about applying SOA to security, to solve interoperability problems, not about "making SOA secure".

I think that too many SOA Security articles focus only on the first meaning of SOA Security (making SOA more secure) than on the second (applying SOA principles to security to make it more easy to deploy and manage).