Cryptography and Network Security

Sometimes we get lot of messages or files from our friends or may be relatives. Have we ever thought whether our friends or relative has sent this or not ??🥴 Usually no, but Don't brood Digital signature helps us to verify that it is your friend or not.  Digital Signature is mathematical model or scheme that is significant for verifying the authenticity of your message.  Lets us understand digital signature with the help of Generic Model (as shown in Fig. 1). Fig.1 : Generic Model of Digital Signature Process Properties Message Authentication protects who exchange two parties who exchange message from any third party. However, it does not protect the two parties against each other.  Suppose Jammu sends an authenticated message to Una. Please consider the following disputes that could arises. A. Una may forge a different message and claim that it came from mandi. Una would simply have to create a message and append an authenticated code using the key that Jammu and Una sh...