Page 50 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

Data Correcting Codes
It’s a technique for encoding data in a manner that enables effortless detection and automatic correction of minor
alterations.
Availability
This refers to the ability of authorized individuals or systems to access information when needed. Availability
ensures that information is accessible and usable. Methods to ensure availability include redundancy, backup and
recovery, and disaster recovery planning.
Tools for Availability
• Physical safeguards and computational redundancies.
Physical safeguards
Physical security involves maintaining the accessibility of information despite physical obstacles. This entails
securing sensitive data and essential information technology within protected environments.
Computational redundancies
It’s employed to enhance resilience against unintended errors. This safeguards computers and storage units that
act as backups in the event of malfunctions.

Concept of Cryptography

Cryptography is the art of securing information and communication by employing codes, ensuring that only
intended recipients can comprehend and handle the data.
This safeguards against unauthorized access.
The term “crypt” signifies “hidden,” and “graphy” denotes “writing.” In cryptography, methods derived from
mathematical principles and algorithms—sets of rule-based calculations—are used to transform messages in
manners that hinder easy decoding.
These algorithms are applied in various tasks like generating cryptographic keys, digital signatures, and verification.
They serve to uphold data privacy, enable secure internet browsing, and safeguard sensitive transactions like
credit and debit card dealings.
Contemporary cryptography revolves around four primary goals:
1 Confidentiality: Ensuring that information remains incomprehensible to anyone other than its intended
recipients.
2 Integrity: Guaranteeing that information cannot be modified during storage or transmission without being
noticed by the intended receiver.
3 Non-repudiation: Preventing the originator/sender of information from disowning their involvement in creating
or sending the information at a later point.
4 Authentication: Enabling both the sender and receiver to verify each other’s identities and the source/
destination of the information.
At its core, cryptography comprises two essential phases:
Encryption and Decryption.
During Encryption, a cipher is applied to the plaintext, converting it into ciphertext. Decryption, on the other hand,
involves using the same cipher to reverse the process, converting the ciphertext back into plaintext.

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CITS : IT&ITES - Computer Software Application - Lesson 01-17