[Requirement] Some [Comments] The information provided by an XKMS service may be confidential, the fact that a party has requested particular information from an XKMS service may allow confidential information to be deduced. Many XKMS applications do not require confidentiality however. [Security Issue] 
Confidentiality
C o n f i d e n t i a l i t y
R e q u e s t A u t h e n t i c a t i o n
R e s p o n s e A u t h e n t i c a t i o n
P e r s i s t e n t A u t h e n t i c a t i o n
M e s s a g e C o r r e s p o n d e n c e
R e q u e s t R e p l a y y
D e n i a l o f S e r v i c e