KeySelector/KeyInfo

The <KeySelector> is an option sent by the client, to tell the server which 
key to sign with.  We want to re-use ds:KeyInfo or ds:KeyInfoType.  There's 
a few ways we could do this:

A) Currently, wd-03 has a ds:KeyInfo inside a dss:KeySelector:

<xs:element name="KeySelector">
     <xs:complexType>
         <xs:sequence>
             <xs:element ref="ds:KeyInfo"/>
         </xs:sequence>
     </xs:complexType>
</xs:element>


B) Juan Carlos suggests the <KeySelector> element could be of type 
ds:KeyInfoType:

<xs:element name="KeySelector" type="ds:KeyInfoType"/>


C) We could use <ds:KeyInfo> directly as an option.


Here's what each choice would look like:

<Options>

     <KeySelector>
         <ds:KeyInfo>
             <ds:X509Data>...</ds:X509Data>
         </ds:KeyInfo>
     </KeySelector>

     <KeySelector>
         <ds:X509Data>...</ds:X509Data>
     </KeySelector>

     <ds:KeyInfo>
         <ds:X509Data>...</ds:X509Data>
     </ds:KeyInfo>

</Options>


Personally, I like (A) - it's more wordy, but it's also the most explicit - 
in (B), it's not immediately clear to a reader that <KeySelector> is a 
ds:KeyInfo, and in (C), it's not immediately clear what function the 
<ds:KeyInfo> is serving.

Trevor