Cryptography Reference
In-Depth Information
7
General Cryptographic Protocols
The design of secure protocols that implement arbitrary desired func-
tionalities is a major part of modern cryptography. Taking the opposite
perspective, the design of any cryptographic scheme may be viewed as
the design of a secure protocol for implementing a suitable functional-
ity. Still, we believe that it makes sense to differentiate between basic
cryptographic primitives (which involve little interaction) like encryp-
tion and signature schemes on one hand, and general cryptographic
protocols on the other hand.
We survey
general
results concerning secure
multi
-party computa-
tions, where the
two
-party case is an important special case. In a nut-
shell, these results assert that one can construct protocols for securely
computing
any
desirable multi-party functionality. Indeed, what is
striking about these results is their generality, and we believe that the
wonder is not diminished by the (various alternative) conditions under
which these results hold.
Our focus on the
general
study of secure multi-party computation
(rather than on protocols for solving specific problems) is natural in
the context of the theoretical treatment of the subject matter. We wish
to highlight the importance of this
general
study to practice. Firstly,
