ration, and invocation of authentication
 modules, that is, <code>ClientAuthModule</code> or <code>ServerAuthModule</code> objects, for a specific message
 exchange within a specific message layer and messaging context.
 
 <p>
 Callers do not directly operate on authentication modules. Instead, they rely on a ClientAuthContext or
 ServerAuthContext to manage the invocation of modules. A caller obtains an instance of ClientAuthContext or
 ServerAuthContext by calling the respective <code>getAuthContext</code