Paper 2012/154
The Joint Signature and Encryption Revisited
Laila El Aimani
Abstract
We study the Sign_then_Encrypt, Commit_then_Encrypt_and_Sign, and Encrypt_then_Sign paradigms in the context of two cryptographic primitives, namely designated confirmer signatures and signcryption. Our study identifies weaknesses in those paradigms which impose the use of expensive encryption (as a building block) in order to meet a reasonable security level. Next, we propose some optimizations which annihilate the found weaknesses and allow consequently cheap encryption without compromising the overall security. Our optimizations further enjoy verifiability, a property profoundly needed in many real-life applications of the studied primitives.
Metadata
- Available format(s)
- -- withdrawn --
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. Unknown status
- Keywords
- Sign_then_EncryptCommit_then_Encrypt_and_SignEncrypt_then_Sign(public) verifiabilitydesignated confirmer signaturessigncryptionzero knowledge proofs.
- Contact author(s)
- laila elaimani @ yahoo fr
- History
- 2017-06-14: withdrawn
- 2012-03-23: received
- See all versions
- Short URL
- https://ia.cr/2012/154
- License
-
CC BY