Collusion-Preserving Computation

In collusion-free protocols, subliminal communication is impossible and parties are thus unable to communicate “any information beyond what the protocol allows”. Collusion-free protocols are interesting for several reasons, but have specifically attracted attention because they can be used to reduce trust in game-theoretic mechanisms. Collusion-free protocols are impossible to achieve (in general) when all parties are connected by point-to-point channels, but exist under certain physical assumptions (Lepinksi et al., STOC 2005) or in specific network topologies (Alwen et al., Crypto 2008). We provide a “clean-slate” definition of the stronger notion of collusion preservation. Our goals in revisiting the definition are: • To give a definition with respect to arbitrary communication resources (that includes as special cases the communication models from prior work). We can then, in particular, better understand what types of resources enable collusion-preserving protocols...

• Type: Journal
• Year: 2012
• Where: CRYPTO
• Authors: Joël Alwen, Jonathan Katz, Ueli Maurer, Vassilis Zikas
• Keywords: CRYPTO 2012, Cryptology, Physical Assumptions, Point Channels, Subliminal Communication