Networksecurity Nd Cryptography

7/30/2019 Networksecurity Nd Cryptography

1/20

NETWORK SECURITY

& CRYPTOGRAPHY

PresentedBy

B.KRISHNATEJA

B.VENUKUMAR


2/20

Introduction

Cryptography

Cryptographic Algorithms

Quantum Cryptography

Advantages of cryptography

Disadvantages ofcryptography

Conclusion


3/20

What is a NETWORK ?

collection of systems connected

together.

Why do Network Security?

As computer systemsbecame more complicated

there was an increasing need for security

Network security is becoming more andmore crucial as the volume of data

being exchanged on the internet increases


4/20

Network Security problems can be

roughly divided into 4closely intertwined

Areas

Privacy

Authentication

Data integrity

Non-repudiation


5/20

Cryptography, is the one of the methods to

provide security.

It involves the use of a cryptographic algorithm

used in the encryption and decryption process.

It works in combination with the key to encrypt

the plain text, and also to decrypt the cipher

text

Cryptography


6/20

Encryption and decryption:-

Encryption means the transformation ofdata by the use of Cryptography to

produce unintelligible data to ensure

confidentiality

The inverse function of encryption is

called as decryption


7/20

Strong

cryptography:-

The result of strong cryptography iscipher text is very difficult to decipher

without possession of the appropriatedecoder tool

How does cryptography works?

A cryptography algorithm, or

Cipher, is a mathematical function used inthe encryption and decryption process.


8/20

Cryptographic

Algorithms:-

Cryptographic algorithms can implementedeither hardware (for speed), or in software (forflexibility). There are 3 classes of algorithms

they are:1. Conventional Cryptography (Symmetric

algorithms, Private keys)

2. Public key Cryptography (Asymmetricalgorithms, public keys)

3. Hash function algorithm.


9/20


10/20

In conventional cryptography, also called secret-key or

symmetric-key encryption, one key is used both for

encryption and decryption. The Data Encryption

Standard (DES) is an example of a conventionalcryptosystem that is widely employed by the U.S.

government.


11/20

public key, which encrypts data, and a corresponding private

key (secret key) for decryption.

It is computationally infeasible to deduce the private key from the

public key.

Anyone who has a public key can encrypt information but cannot

decrypt it. Only the person who has the corresponding private key

can decrypt the information.


12/20

Basically handwritten signature is easy tocounterfeit. A digital signature is superior to ahandwritten signature in that it is nearly impossible to

counterfeit, plus it attests to the contents of theinformation as well as to the identity of the signer.


13/20

Hash functions

A one-way hash function takes

variable-length input in this case, a message of

any length, even thousands or millions of bits

and produces a fixed-length output

PGP uses a cryptographically strong hash

function on the plaintext the user is signing.

This generates a fixed-length data item knownas a message digest


14/20


15/20

it is based on usage of particles/waves of light(PHOTONS) and their intrinsic properties to developan unbreakable cryptographic system

Eaves dropping concept System works on the principle of Heisenberg principle


16/20

Advantages:-

Based on natural quantum laws

Computational Complexity Expires.

There is no expiration date on thesecurity of QC messages.

Perfect for public communication

Easy to detect an eavesdropper.


17/20

Disadvantages

Severally limited by technology

Practical systems are limited by distance.

Photon emitters and detectors are farfrom perfect, causing a lot of errors.

Most protocols require a classical

channel.


18/20

Conclusion

As the proverb says that Even a crow

can peck an elephant which is stuck in the mud. Even

though we are providing high security by cryptographythere are many pitfalls in it also. Nothing in the world is

100% secured.

Cryptography is one of the way to providenetwork security but it is not only the path to achieve

network security.


19/20

Any

?


20/20

THANK YOU

Networksecurity Nd Cryptography

Documents

Transcript of Networksecurity Nd Cryptography