Cryptography Essay

University of Sharjah

College of Business Administration

Department of Management Information Systems

0303450 - Information security

Project Title: Cryptography

Fall 2015-2016

Group Members:

Maitha Al Hammadi U00026484

Enas

Mariam

Arwa

Submitted to: Dr.Saadat Mehmood Alhashmi

Introduction:

Mariam

Literature review:

Enas

Cryptography goals:

Cryptography concerns on four main goals:

1- Message Confidentiality: only an authorized recipient should be able to extract the contents of the message.

2- Message Integrity: the recipient should be able to determine if the message have been altered.

3- Sender Authentication: the recipient should

It is also called as public key encryption as the user publicly distributes one of the keys without a care of secrecy. In the case of confidential message to the user, they distribute the encryption key. Asymmetric encryption relies on the fact that possession of the encryption key will not reveal the decryption key. Moreover, digital signature is form of authentication with some parallels to public key encryption. The two keys are the public verification key and secret signature key. As in public key encryption, the verification key can be distributed to other people with the same caveat that the distribution process should in some way authenticate the owner of the secret key. Security relies on the fact that possession of the verification key will not reveal the signature

It implemente crypto functions and allows you to learn and use methods.

The methods available include both classic methods (e.g. the Caesar encryption algorithm) and modern cryptosystems (for example, the RSA and AES algorithms, as well as algorithms based on elliptic curves).

Automatic analysis tools for obtaining the key, starting from a knowledge of the encrypted document and any additional information (the unencrypted document or language of the document), are provided for the classic encryption algorithms. In order to support your own analysis of documents, CrypTool can display a histogram of the document, calculate the statistics for any N-grams and the entropy and autocorrelation.

Here are two examples of Encrypt/Decrypte by using some methods:

1- Example one : Caesar algorithm

To start with this program you have to click on file> new from the menu above. Then, you will get a white screen to place your paragraph in. After you have placed the text bellow, click on Encrypt/Decrypt> symmetric (classic)> Caesar /