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
- Version: Specifies the X.509 version (usually v3).
- Serial Number: A unique identifier for the certificate issued by the Certificate Authority (CA).
- Signature Algorithm: The algorithm used by the CA to sign the certificate (e.g., RSA or ECDSA).
- Issuer: The CA that issued the certificate (e.g., “CN=Example CA”).
Network Fundamentals Exam (Version 4.0)
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Read MoreSorting, 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];
Read More
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)
Read MoreDBMS 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
Read MoreCache 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:
- Which system has a lower miss rate: a 16KB instruction cache and a 16KB data cache, or a unified 32KB cache?
- 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