Encryption And Decryption

Description

ABSTRACT

LAN encryption is used to secure your wireless network with an authentication protocol that requires a password or network key when a user or device tries to connect. If your wireless network is not secured with some type of encryption, unauthorized users could access your network and obtain personal information or use your Internet connection for malicious or illegal activity. Also, your network speed or performance may decrease if people are using your network without your knowledge.

The process of encryption hides data or the contents of a message in such a way that the original information can be recovered through a corresponding decryption process. Encryption and decryption are common techniques in cryptography, the scientific discipline behind secure communications.

Many different encryption / decryption processes or algorithms exist. It turns out that in cryptography, it’s very difficult to keep the logic of an algorithm truly secret. Especially on the Internet, it’s generally much easier to use well-known public algorithms, and rely on alternative forms of protection.

This project comes into use when we want the data communication to be protected from others. During war times, when a particular base wants to send a message to remotely located units which belong to the same army, in between any third party can trap the data when it is transmitted in wires or wireless.

The essence of this project comes into this particular scene of the military world. Our project protects the data from strangers. This is achieved by incorporating a new wireless network system in which data is code modulated and then encrypted to get an encoded version of the data to be transmitted.

A given encryption algorithm takes the original message, and a key, and alters the original message mathematically based on the key’s bits to create a new encrypted message. Likewise, a decryption algorithm takes an encrypted message and restores it to its original form using one or more keys.

Some cryptographic algorithms use a single key for both encryption and decryption. Such a key must be kept secret; otherwise, anyone who had knowledge of the key used to send a message could supply that key to the decryption algorithm to read that message.

Other algorithms use one key for encryption and a second, different key for decryption. In this case the encryption key can remain public, because without knowledge of the decryption key, messages cannot be read.

TABLE OF CONTENT

COVER PAGE

CERTIFICATION

DEDICATION

ACKNOWLEDGEMENT

TABLE OF CONTENT

CHAPTER ONE

INTRODUCTION

BACKGROUND OF THE STUDY

AIM/OBJECTIVE OF THE STUDY

PURPOSE OF THE STUDY

APPLICATION OF THE STUDY

CHAPTER TWO

LITERATURE REVIEW

REVIEW OF THE STUDY

CHAPTER THREE

3.1 LAN SECURITY SOLUTION

3.2 DETECTING AND RESPONDING TO INTRUDERS

3.3 COUNTRY SPECIFIC LAW

3.4 LAN ENCRYPTION

3.5 TYPES OF ENCRYPTION

3.6 ENCRYPTION AND DECRYPTION ALGORITHM

3.7 BACKGROUND OF ENCRYPTION AND DECRYPTION ALGORITHM

3.8 TYPES OF CRYPTOGRAPHIC ALGORITHMS

3.9 SYMMETRIC KEY CRYPTOGRAPHY

CHAPTER FOUR

4.1 CIPHER

4.2 CODE (CRYPTOGRAGHY)

4.3 HISTORICAL

4.4 MODERN OF ENCRYPTION

4.5 DIFFERENCE BETWEEN SYMMETRIC AND ASYMMETRIC KEYS

CHAPTER FIVE

5.1 KEY MANGEMENT

5.2 TYPES OF KEY

5.3 KEY EXCHANGE

5.4 KEY STORAGE

5.5 KEY USE

5.6 PUBLIC KEY INFRASTRUCTURE (PKI)

5.7 ENTERPRISE KEY AND CERTIFICATE MANAGEMENT (EKCM)

5.8 MULTICAST GROUP KEY MANAGEMENT

5.9 CHALLENGES OF KEY MANAGEMENT

CHAPTER SIX

6.1 CONCLUSION

6.2 REFERENCES

CHAPTER ONE

1.0                                        INTRODUCTION

1.1                          BACKGROUND OF THE STUDY

Encryption is the process of encoding messages (or information) in such a way that eavesdroppers or hackers cannot read it, but that authorized parties can. In an encryption scheme, the message or information (referred to as plaintext) is encrypted using an encryption algorithm, turning it into an unreadable cipher text. This is usually done with the use of an encryption key, which specifies how the message is to be encoded. Any adversary that can see the cipher-text should not be able to determine anything about the original message. An authorized party, however, is able to decode the cipher text using a decryption algorithm, that usually requires a secret decryption key, that adversaries do not have access to. For technical reasons, an encryption scheme usually needs a key-generation algorithm to randomly produce keys.

There are two basic types of encryption schemes: Symmetric-key and public-key encryption. In symmetric-key schemes, the encryption and decryption keys are the same. Thus communicating parties must agree on a secret key before they wish to communicate. In public-key schemes, the encryption key is published for anyone to use and encrypt messages. However, only the receiving party has access to the decryption key and is capable of reading the encrypted messages. Public-key encryption is a relatively recent invention: historically, all encryption schemes have been symmetric-key (also called private-key) schemes.

Encryption has long been used by militaries and governments to facilitate secret communication. It is now commonly used in protecting information within many kinds of civilian systems. For example, the Computer Security Institute reported that in 2007, 71% of companies surveyed utilized encryption for some of their data in transit, and 53% utilized encryption for some of their data in storage. Encryption can be used to protect data “at rest”, such as files on computers and storage devices (e.g. USB flash drives). In recent years there have been numerous reports of confidential data such as customers’ personal records being exposed through loss or theft of laptops or backup drives. Encrypting such files at rest helps protect them should physical security measures fail. Digital rights management systems which prevent unauthorized use or reproduction of copyrighted material and protect software against reverse engineering (see also copy protection) is another somewhat different example of using encryption on data at rest.

Encryption is also used to protect data in transit, for example data being transferred via networks (e.g. the Internet, e-commerce), mobile telephones, wireless microphones, wireless intercom systems, Bluetooth devices and bank automatic teller machines. There have been numerous reports of data in transit being intercepted in recent years. Encrypting data in transit also helps to secure it as it is often difficult to physically secure all access to networks^.

Encryption, by itself, can protect the confidentiality of messages, but other techniques are still needed to protect the integrity and authenticity of a message; for example, verification of a message authentication codes (MAC) or a digital signature. Standards and cryptographic software and hardware to perform encryption are widely available, but successfully using encryption to ensure security may be a challenging problem. A single slip-up in system design or execution can allow successful attacks. Sometimes an adversary can obtain unencrypted information without directly undoing the encryption.

One of the earliest public key encryption applications was called Pretty Good Privacy (PGP). It was written in 1991 by Phil Zimmermann and was purchased by Symantec in 2010.

Digital signature and encryption must be applied at message creation time (i.e. on the same device it has been composed) to avoid tampering. Otherwise any node between the sender and the encryption agent could potentially tamper it. It should be noted that encrypting at the time of creation only adds security if the encryption device itself has not been tampered with.

1.2                        AIM / OBJECTIVE OF THE STUDY

The main objective of our project is to encrypt/decrypt the multimedia files for personal and professional security. Encryption and Decryption protects privacy of our email messages, documents and sensitive files by encrypting them to provide high protection against unauthorized data access.

1.2                                PURPOSE OF THE STUDY

The purpose of this work is to ensure high level of security in our internet or wireless network.

1.3                          SIGNIFICANCE OF THE STUDY

1.     Security for Data at All Times: Generally, data is most vulnerable when it is being moved from one location to another. Encryption works during data transport or at rest, making it an ideal solution no matter where data is stored or how it is used. Encryption should be standard for all data stored at all times, regardless of whether or not it is deemed “important”.

2.     Data Maintains Integrity: Hackers don’t just steal information, they also can benefit from altering data to commit fraud. While it is possible for skilled individuals to alter encrypted data, recipients of the data will be able to detect the corruption, which allows for a quick response to the cyber-attack.

3.     Protects Privacy: Encryption is used to protect sensitive data, including personal information for individuals. This helps to ensure anonymity and privacy, reducing opportunities for surveillance by both criminals and government agencies. Encryption technology is so powerful that some governments are attempting to put limits on the effectiveness of encryption—which does not ensure privacy for companies or individuals.

4.     Protects Data across Devices: Multiple (and mobile) devices are a big part of our lives, and transferring data from device to device is a risky proposition. Encryption technology can help protect store data across all devices, even during transfer. Additional security measures like advanced authentication help deter unauthorized users.

1.4                                          APPLICATIONOF THE STUDY

Encryption and decryption protects the communications of individuals and organizations from unsophisticated and sophisticated criminals and repressive governments. It assures the security of electronic commerce transactions over the Internet—for example making it possible to transmit credit card numbers. It protects information stored on smartphones, laptops, and other devices. Encrypted communication capabilities are built into major computing platforms and in an array of messaging applications that are used by hundreds of millions of users.

Computer and communications systems use cryptography for three broad purposes—to protect the confidentiality of information (i.e., encryption), to protect the integrity of information, and to authenticate the originator or sender of information. Applications that require the secrecy of large volumes of information use symmetric cryptography. Asymmetric (public key) cryptography is frequently used to securely disseminate keys that are used in symmetric cryptography. For example, cryptography enables the secure distribution of regular software updates, including security patches, over a network and is used to verify the identity of individuals and organizations. This report focuses largely on the first application, encryption protecting confidentiality. However, it touches on another use of cryptography: schemes to provide exceptional access to information stored on smartphones or laptops that are locked with a passcode may involve modifications to the cryptography that implements the locking mechanism.

The increased availability and use of encryption—most notably to protect access to data stored on smartphones and to keep Internet messages confidential—means that it is increasingly encountered in investigations by law enforcement and intelligence agencies.

1.6                                                         PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work,   chapter two presents the literature review of the study,  chapter three describes the methods applied,  chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.