The classical communication channel must be authenticated using an unconditionally secure authentication scheme.
The problem - and because Microsoft had an authentication scheme.
Naccache and Frémanteau provided an authentication scheme in 1992 for memory cards.
So that's the first of a multifactor authentication scheme would be that.
Computer communications already costs too much- adding cryptographic encoding and elaborate authentication schemes will only make it worse.
This property can be used to break naive authentication schemes based on hash functions.
These can range from server-side programming language support to authentication schemes.
Hotmail will also offer an interesting new authentication scheme.
And some manufacturers of multifactor authentication schemes are now getting to the point they must become accessible.
This means that any authentication scheme can be used, including passwords or certificates.