(2) and (3) could be achieved through MACs and Digital Signatures. (1) could be achieved using encryption/decryption mechanism. Authenticity: When Bud receives a message from Ankita, He can be sure it is from Ankita and not from Mayank.Īnother feature that we might want is deniability, i.e., if someone recovers Ankita’s or Bob’s old messages in future, it can’t be linked to them and they can deny having sent that message.Integrity: If Bud receives a message from Ankita, He can check if the message was modified by Mayank on the way.Confidentiality: Mayank can’t know what messages Ankita and Bud send to each other.We want our system to have the following properties: Mayank is evil, and he wants to listen on the conversation between Ankita and Bud, and possibly want to send messages to Ankita acting as Bud and to Bud acting as Ankita. Ankita and Bud want to exchange messages. The names are chosen based on their roles). ( Cryptography literature uses Alice, Bob, and Mallory. So what possible features such system should have? I will introduce a few characters in the system. Purpose of this post is to give you the sneak peek of what is actually happening behind the scene.
So as long as underlying cryptography is intact, you can be assured that no one else other than your friend knows about your dirty little secret. In layman’s words, every message that you sent to your friend, is encrypted on your device, this encrypted message passes through network and a whole bunch of servers, reaches your friend’s device, and finally, it is decrypted on friend’s device. You must have heard about WhatsApp using end to end encryption. “Matrix movie still” by Markus Spiske on Unsplash
0 kommentar(er)
