158 WebSphere and .Net Interoperability Using Web Services
back by the assessor. When the assessor receives this reference, they know
which database entry it refers to. Thus, we see a third use of WS-Addressing: it
enables stateful interaction in which, rather than each message exchange being
one-off, messages can form a series. Note also that the LGI system does not
have to understand the <assessor:AssessmentID> tag that is returned within the
<wsa:ReferenceProperty>. The LGI system simply knows that this reference is
being used to identify this particular communication session and that it must
include it when it replies to the assessor. The introduction of just one new
element (the wsa:ReferenceProperty) gives us the immense power of stateful ...