On the project that i'm currently working, we authenticate the clients by username and password. In this system each user has a key which is calculated from his password. However, we want to provide ...
Say we're using a shared key between two parties, that has been distributed using public key encryption, is it still necessary to sign any data that's encrypted using the shared key? Or is it enough ...
If I have a message that I need to send to another person, how do I achieve non repudiation ? Is digitally signing the message sufficient ?