INFORMATION SECURITY

TECHNIQUES

PREVENTION DETECTION RESPONSE RECOVERY

SECURITY MEASURES

PREVENTION

DETECTION

RESPONSE

RECOVERY

PREVENTION

Cryptography

Steganography

Digital Watermarking

CRYPTOGRAPHY

CRYPTOLOGY

CRYPTOGRAPHY

CRYPTANALYSIS

TERMINOLOGY:

General Model of  CRYPTOGRAPHIC SYSTEM

Types of ENCRYPTION

SYMMETRIC Encryption

ASYMMETRIC

Encryption

Dear AliI have received the new

Dear AliI have received the new

Dear Ali I have

received the new

Symmetric Key Encryption

Encryption Decryption

Original Data

Original Data

Jumbled Data

Symmetric Key

Symmetric Key

(Conventional /private key Encryption)

Asymmetric EncryptionAsymmetric Key Encryption

Cryptosystems offer 3 important services: 1. Secrecy , which refers to the

denial of access to info. by unauthorized users

2. Authenticity , which refers to the validation of the source of a message

3. Integrity , which refers to the assurance that a message was not modified by accidental or deliberate means to transit. 

APPLICATION:Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL), are cryptographic protocols which are designed to provide communication security over the Internet.

They use X.509 certificates and hence asymmetric cryptography to assure the counterparty with whom they are communicating, and to exchange a symmetric key.

Several versions of the protocols are in widespread use in applications such as

Web Browsing Email Instant Faxing Instant messaging Voice-over-IP (VoIP)

STEGANOGRAPHY

Types of Steganograp

hy

Pure Secret Key

Public Key

PURE STEGANOGRAPHY

ADVANTAGE :

DISADVANTAGE :

Reduces the difficulty in key sharing.

Doesn’t provide better security because it is easy to extract the message if the unauthorized person knows the embedding method.

SECRET-KEY STEGANOGRAPHY

Provides better security compared to Pure Steganography

Difficulty in sharing the secret key. If the attacker knows the key it will be easier to decrypt and access original information.

ADVANTAGE :

DISADVANTAGE :

PUBLIC-KEYSTEGANOGRAPHY

DIGITALWATERMARKING

Watermark

WATERMARKING

Robust Fragile Visible Invisible

APPLICATIONS OF WATERMARKING

Copyright protection

Monitoring

Content manipulation indication

Document Security

References:Newton, David E.

(1997). Encyclopaedia of Cryptography. Santa Barbara California

Simon Haykin(2010), Communication Systems

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MADE BY:JAYPRIYA

CSE(EVE) 2nd Yr