4、In order to satisfy the requirement of non-repudiation, you need both message authentication and sender authentication simultaneously.
3、What you should note here is that message authentication guarantees nothing about who sent that message.
5、The construction of a provable hash algorithm is developed based on the operations from various groups, also, a safety message authentication code is presented by the result.
2、message authentication codes, and so on.
1、identity authentication,encryption and message authentication or message signed mechanism.
