Cryptography simple report

[seminar addict]

Cryptography simple report

[attachment=15951]

What is Cryptography?

This is the art of
keeping messages
secret


Secret Key Cryptography-

Follows SYMMETRIC
ALGORITHMS.
Single key used to
encrypt and decrypt.
Key must be known
by both parties.

Public Key Cryptography-

Follows ASYMMETRIC
ALGORITHMS.
Each entity has 2 keys:
private key (a secret)‏
public key (well known)‏

Using Keys


Private keys are used for
decrypting.
Public keys are used for
encrypting.
encryption
plaintext ----------------- ciphertext

public key

decryption
Ciphertext ----------------- plaintext

private key

Message Digest

Also known as “hash function” or “one-way
transformation”.

Transforms a message
of any length and
computes a fixed
length string.

Need of Digest-
Alisha could just encrypt her name, and then
Bijay could decrypt it with IMAGE