We propose a scheme for electronic cash based on symmetric primitives. The scheme is secure in the framework for universal compos-ability assuming the existence of a symmetric CCA2-secure encryption scheme, a CMA-secure signature scheme, and a family of one-way, collision-free hash functions. In particular, the security proof is not in the random-oracle model. Due to its high efficiency, the scheme is well-suited for devices such as smart-cards and mobile phones. We also show how the proposed scheme can be used as a group signature scheme with onetime keys.
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