A globally unique identifier (GUID) for a specific revision of an update.

Defined in namespace: http://www.microsoft.com/SoftwareDistribution.

 <s:complexType name="UpdateIdentity">
     <s:element minOccurs="1" maxOccurs="1" name="UpdateID" 
        type="s2:guid" />
     <s:element minOccurs="1" maxOccurs="1" name="RevisionNumber" 
        type="s:int" />

UpdateID: A GUID that identifies an update.

RevisionNumber: A 32-bit number that uniquely identifies a specific version of an update. These types are specified in the Abstract Data Model (section 3.1.1).