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On the Construction of VariableInputLength Ciphers
 In Fast Software Encryption
, 1998
"... We invesitgate how to construct ciphers which operate on messages of various (and effectively arbitrary) lengths. In particular, lengths not necessarily a multiple of some block length. (By a "cipher" we mean a keyindexed family of lengthpreserving permutations, with a "good" cipher being one that ..."
Abstract

Cited by 15 (4 self)
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We invesitgate how to construct ciphers which operate on messages of various (and effectively arbitrary) lengths. In particular, lengths not necessarily a multiple of some block length. (By a "cipher" we mean a keyindexed family of lengthpreserving permutations, with a "good" cipher being one that resembles a family of random lengthpreserving permutations.) Oddly enough, this question seems not to have been investiaged. We show how to construct variableinput length ciphers starting from any block cipher (ie, a cipher which operates on strings of some fixed length n). We do this by giving a general method starting from a particular kind of pseudorandom function and a particular kind of encryption scheme, and then we give example ways to realize these tools from a block cipher. All of our constructions are proven sound, in the provablesecurity sense of contemporary cryptography. Variableinputlength ciphers can be used to encrypt in the presence of the constraint that the ciphertex...
Supporting FaultTolerant Distributed Computations under RealTime Requirements
, 1991
"... In contrast to conventional (trans)action concepts the proposed dynamic action model includes the possibility for optimistic recovery in order to gain high efficiency during normal operation. To minimize time overhead we use a redundant recovery graph to record the necessary recovery information. Ba ..."
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Cited by 8 (5 self)
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In contrast to conventional (trans)action concepts the proposed dynamic action model includes the possibility for optimistic recovery in order to gain high efficiency during normal operation. To minimize time overhead we use a redundant recovery graph to record the necessary recovery information. Based on this graph we provide decentralized protocols that efficiently produce a consistent system state concurrent to normal system activity. Considering realtime applications in distributed systems, error processing time has to be minimized. To achieve this, the proposed concept is extended to the parallel dynamic action scheme where the different versions are executed in parallel. This leads to a recovery concept that combines efficient distributed processing during normal operation and prompt reaction in case of an error . 1. Introduction Fault tolerant systems [AnLe81] provide continious operation in spite of errors denoting an erroneous system state that is created due to the occurren...