What is a Digital Signature?
- A digital signature is like a virtual fingerprint or seal that ensures the authenticity of a digital message or document. It helps verify that the message or document has not been altered and comes from the claimed sender.
Three Key Algorithms:
- Key Generation:
- Think of this like creating a pair of keys – a private key and a public key.
- The private key is a secret key that the sender keeps to themselves.
- The public key is shared with others.
- Signing Algorithm:
- This algorithm takes the message and the private key to create a unique signature.
- It’s like putting a special stamp on the message that only the sender can create.
- Signature Verifying Algorithm:
- This algorithm, on the receiving end, takes the message, the signature, and the public key.
- It checks if the signature matches the message and if it was indeed created by the private key associated with the public key.
- If everything checks out, the message is considered authentic.
Visualizing the Process:
- Imagine there’s a sender and a receiver.
- The sender has a private key and a public key.
- The sender uses the private key and the message to create a unique signature.
- The sender sends the message along with the signature to the receiver.
- The receiver uses the sender’s public key to check if the signature matches the message.
- If it matches, the message is considered valid; if not, something might be fishy.