3.1.4 Message Processing Events and Sequencing Rules

The following table summarizes the list of operations as defined by this specification:

Operation	Description
SignMessage	This operation causes a SAML Message signature be applied to the supplied SAML Message when the configuration requires signing, with the resulting message being returned as a result.
VerifyMessage	This operation verifies whether a SAML Message is from a known party and signed according to metadata directives for that party, returning the result as a Boolean.
Issue	This operation causes issuance of a SAML token.
Logout	This operation causes a SAML session to be logged out.
CreateErrorMessage	This operation creates a SAML error message, applying a signature, if the configuration for the requested principal specifies that messages are to be signed.

For each operation there is a request and reply message. In all cases, the sequence of operation is that the client sends the request message to the server, which responds with the corresponding reply message. The server MUST accept the request messages and the client MUST accept the corresponding reply messages, when sent in response to a request message. The behavior of any other uses of these messages is undefined.