Possible additional to the reference model

Hello,

Thanks for the writeup.

I think there is two things that is not covered by the reference model, 
that I think is within the scope of the Architecture of SOA.

Consumers: Mentioned in many places. But not placed in any of the 
concept-ellipses. Why I think it is important for SOA - You need to take 
into account who is the target. And you might loose control of usage of 
your system. ( might be categorized under the policy ) - One of my 
recommendations is always to have some kind of authentication, even if 
your service is completely free.

Further: Services tend to grow, great services grows even faster. And 
yes x in XML is for extendability :) But you need to think this into our 
architecture. At some point you might need to break backwards 
compatibility with older version...

That was my two cents,

./Morten