Phan, Raphael Chung-WeiVaudenay, Serge2009-06-082009-06-082009-06-08200910.1007/978-3-642-01877-0_17https://infoscience.epfl.ch/handle/20.500.14299/40358We give two impossibility results regarding strong encryption over an infinite enumerable domain. The first one relates to statistically secure one-time encryption. The second one relates to computationally secure encryption resisting adaptive chosen ciphertext attacks in streaming mode with bounded resources: memory, time delay or output length. Curiously, both impossibility results can be achieved with either finite or continuous domains. The latter result explains why known CCA-secure cryptosystem constructions require at least two passes to decrypt a mes- sage with bounded resources.text::conference output::conference proceedings::conference paper