CWI Cryptology Group

Abstract: Algorithmic progress and future technology threaten today's cryptographic protocols. Long-term secure protocols should stay secure, even if the adversary gets practically unlimited computational power *after* protocol execution (e.g., he stores some data from the protocol until he is able to break the underlying complexity assumptions).
We study the notion of long-term UC, i.e., of protocols that are long-term secure and universally composable simultaneously. We introduce the notion and then present some impossibility and possibility results.