An efficient identity-based online/offline encryption scheme

Joseph K Liu, Jianying Zhou

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

42 Citations (Scopus)


In this paper, we present an efficient Identity-based Online / Offline Encryption (IBOOE) scheme. An IBOOE scheme allows one to split the encryption into two phases. In the offline phase, most heavy computations such as exponentiation or pairing, if any, are done in this phase. Yet it does not require the knowledge of the plaintext or the receiver s identity. This nice property allows it can be executed offline , or inside some powerful device. The next phase is called the online phase, where only light computations such as integer addition, multiplication or hashing are needed, together with the plaintext and the receiver s identity. This can be executed inside some embedded device such as smart card or wireless sensor where the computation power is very limited. We propose an efficient IBOOE scheme, with great improvement in the computation requirement of both the offline, online encryption phase and decryption phase, together with much shorten ciphertext over previous schemes. Our scheme can be proven secure in the random oracle model.
Original languageEnglish
Title of host publicationProceedings of the 7th International Conference on Applied Cryptography and Network Security (ACNS 2009)
EditorsMichel Abdalla, David Pointcheval, Pierre-Alain Fouque, Damien Vergnaud
Place of PublicationHeidelberg Germany
Pages156 - 167
Number of pages12
ISBN (Print)9783642019562
Publication statusPublished - 2009
Externally publishedYes
EventInternational Conference on Applied Cryptography and Network Security 2009 - Paris-Rocquencourt, France
Duration: 2 Jun 20095 Jun 2009
Conference number: 7th (Proceedings)


ConferenceInternational Conference on Applied Cryptography and Network Security 2009
Abbreviated titleACNS 2009
Internet address

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