Cryptography Essentials: Keys, Hashes, and Authentication

X.509 Certificate Format

An X.509 certificate is a digital certificate used to establish the identity of an entity, such as a person or a website, and ensure secure communication.

Key Components

  1. Version: Specifies the X.509 version (usually v3).
  2. Serial Number: A unique identifier for the certificate issued by the Certificate Authority (CA).
  3. Signature Algorithm: The algorithm used by the CA to sign the certificate (e.g., RSA or ECDSA).
  4. Issuer: The CA that issued the certificate (e.g., “CN=Example CA”).
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Network Fundamentals Exam (Version 4.0)

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Sorting, Heaps, and Graph Algorithms

Merge sort:


#include <stdio.H>

#include <stdlib.H>

#include <string.H>

#define MAX 10000

Int noofcomparision = 0;


Void merge(int arr[], int l, int mid, int h) {

Int n1 = mid + 1 – l;


Int n2 = h – mid;


Int a[n1], b[n2];


For (int i = 0; i < n1; i++) {

A[i] = arr[i + l];


    }

For (int i = 0; i < n2; i++) {

B[i] = arr[i + mid + 1];


    }

Int i = 0, j = 0, k = l;


While (i < n1 && j < n2) {

Noofcomparision++;


        if (a[i] <= b[j]) {

            arr[k] = a[i];

 

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Understanding Computer Fundamentals: Data, Devices, and Memory

Why People Prefer Computers

Computers work faster than humans, find information quickly, store data efficiently, and operate tirelessly.

Data Types

Numeric: Integer and real.

Text: String.

Graphics: Pictures.

Date

Sound

Input Devices

Concept Keyboards

A flat board with programmable keys, used in primary education.

Light Pen

A pen-shaped wand with light sensors to select objects on screen.

Touch Screen

A flat screen that detects touch using infrared lasers, commonly found in restaurants.

OMR (Optical Mark Recognition)

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DBMS Essentials: Organization, Integrity, and Access

Database Management Systems (DBMS)

A DBMS is a software suite designed to access and manage databases. A database is a structured collection of related data.

Challenges of File Management

  • Data Redundancy and Inconsistency: Data duplication across various files and formats.
  • Physical-Logical Data Dependency: Changes in data structure require program modifications.
  • Difficulty in Data Access: Accessing data requires specific program code for each query.

Database Systems

A database is a large, organized store

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Cache and Virtual Memory Management

Cache and Virtual Memory

Cache Analysis

Considering the data and the accompanying table for direct correspondence with caches and block size of 32 bytes, taken on a set of test programs where the percentage of references to instructions is 75%, answer the following:

  1. Which system has a lower miss rate: a 16KB instruction cache and a 16KB data cache, or a unified 32KB cache?
  2. Assume a cache hit takes one clock cycle, a miss costs 50 cycles, and a hit in a load or store requires an extra cycle in the case
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