Question

How does cryptography enhance security? When is the use of cryptography not justified?

Answer 1

Cryptography is fundamentally a technology that is used widely to encrypt and decrypt messages. In its most basic definition, cryptography is nothing but the art and science of writing or solving codes.

Hence, it is easily understandable that cryptography is helpful to us in hiding the secret information while sending them over a network. It ensures that our private message is not understood to all people even if we send them in public network and is meaningful only for the intended person.

Security aspects of information sharing involves authentication, Confidentiality and Integrity. Cryptography provides us with all of these.
Authentication means the process of identifying an individual based on some unique signatures. So that the sender or source of the message can be identified.
Confidentiality maintains the secrecy of the information. Even if the message is passed to everybody, only the authorized person with the key and knowing the decryption mechanism can actually extract out information out of the message.
The term Integrity ensure that the message that was initiated at the source end is recieved exactly at the receiver end without any loss of data or alterations to it.

So,cryptography enhances security by checking on all these three aspects and overlooking of any of these three would mean the use of cryptography is not justified.