efa A good authentication scheme is ■■ Sound: an honest party can successfully authenticate him/herself Non-transferable No impersonation all this is true even when a large number of authentications are observed Eve is able to spoofleavesdrop Multiple instances are run simultaneously 復大辱软件学院6 A good authentication scheme is… • Sound: an honest party can successfully authenticate him/herself • Non-transferable • No impersonation • All this is true even when – A large number of authentications are observed – Eve is able to spoof/eavesdrop – Multiple instances are run simultaneously