Networking and Database Concepts PDF

Networking Concepts Database Concepts Router: Connects multiple networks Database: An organized collection of and directs data packets to their data, typically stored and accessed destination. electronically from a computer s...

Networking Concepts Database Concepts Router: Connects multiple networks Database: An organized collection of and directs data packets to their data, typically stored and accessed destination. electronically from a computer system. Star Topology: A network where all Relational Database Model: A type of devices are connected to a central hub database structure that stores data in or switch. It’s easy to manage, and the tables, allowing relationships between failure of one device doesn’t affect the different data items using keys. network, but if the hub fails, the entire SQL (Structured Query Language): A network is disrupted. standardized language used to manage Firewall: A security system that and manipulate relational databases, monitors and controls incoming and including operations like querying, outgoing network traffic based on updating, and deleting data. predetermined security rules. Oracle: A popular database HTTP: The protocol used for management system that uses the transmitting web pages. Its secure relational model to store and manage version, HTTPS, encrypts data for data. secure communication. Foreign Key: A field in a table that Repeater: A network device that uniquely identifies a row in another amplifies and retransmits signals to table, establishing a relationship extend the range of a network. between two tables. Modem: A device that converts digital Hierarchical Database Model: data into analog signals for Organizes data in a tree-like structure, transmission over telephone lines and where each record has a single parent vice versa, providing internet access. and potentially many children. Ring Topology: A network where Data Redundancy: The unnecessary devices are connected in a ring. Data duplication of data within a database, flows in one direction, and while it which can lead to storage ensures efficient data transmission, a inefficiencies and maintenance failure in the ring can disrupt the challenges. entire network. Normalization: The process of SMTP (Simple Mail Transfer organizing a database to reduce Protocol): A protocol used to send redundancy and improve data and receive emails over the internet. integrity by dividing larger tables into Bridge: A device used to filter and smaller, manageable ones. forward traffic between two network RDBMS (Relational Database segments, improving performance and Management System): A system for dividing traffic. managing relational databases, where data is stored in tables that are related to each other using keys. Software Development Parallel Conversion: A method of Concepts transitioning from an old system to a new one, where both systems operate SDLC (Software Development Life simultaneously for a period of time. Cycle): A structured approach to software development, which includes Web Development Concepts phases like planning, analysis, design, implementation, testing, and Wireframe: A basic visual maintenance. representation or blueprint of a Analysis Phase: The stage where website’s layout, showing the system requirements are gathered and structure and navigation without analyzed to ensure the software will detailed design. meet the needs of its users. HTML: Hypertext Markup Language, Scope Creep: The tendency for the the standard language for creating scope of a project to expand beyond its web pages and web applications. original objectives, often due to adding Static Website: A website where the new features or requirements without content is fixed and doesn’t change proper control. unless manually updated. Predictive Development: A Dynamic Website: A website that development approach that follows a displays different content based on well-defined and linear sequence, like user interactions, time of day, or other the Waterfall model. variables. Agile Development: An iterative and URL (Uniform Resource Locator): A collaborative approach to software reference or address used to access development where requirements and resources on the internet. solutions evolve through cross- Web Server: A system that stores, functional teamwork. processes, and delivers web pages to DevOps: A combination of clients (browsers) via the internet. development and operations practices JavaScript: A programming language aimed at shortening the systems used to create dynamic and interactive development life cycle and providing effects within web browsers. continuous delivery of high-quality Web Hosting: A service that allows software. individuals or organizations to publish Gantt Chart: A type of bar chart used their website on the internet. in project management to visually IP Address: A unique string of represent the timeline of tasks and numbers assigned to devices activities in a project. connected to the internet, used to Penetration Testing: A security identify and locate them. testing method used to identify vulnerabilities in a system by simulating attacks. What is Binary? For example, for an 8-bit binary number (which is one byte), the place The binary system is a base-2 values are: numeral system that represents values 2^7 = 128 using only two symbols: 0 and 1. These two symbols correspond to the 2^6 = 64 two possible states of an electronic circuit (off and on), making binary the 2^5 = 32 language of computers. 2^4 = 16 Unlike the decimal system (base-10), 2^3 = 8 which uses 10 digits (0-9), binary 2^2 = 4 relies on just two symbols to represent all numeric values. 2^1 = 2 Binary in Computers 2^0 = 1 When a binary number is written, the In computers, data is stored, value of each bit is determined by its processed, and transmitted in binary position and the corresponding power form. Each binary digit (bit) can of 2. represent two possible states: 0: Off, false, or no current. Converting Binary to Decimal 1: On, true, or current. To convert from binary to decimal, take each bit (starting from the right), Because of its simplicity, binary is multiply it by its corresponding power well-suited for electronic circuits, of 2, and then sum the results. where a bit can be represented as an electrical signal, with 1 being “high Example: Convert 1011_2 to decimal: voltage” (on) and 0 being “low voltage” (off). 1. The binary number is 1011_2. 2. Starting from the rightmost bit, Place Value in Binary assign the powers of 2: In the binary system, each position in a The rightmost bit (1) is in number has a place value that is a the 2^0 place, so: 1 \times 2^0 = 1. power of 2. This is similar to how in the decimal system, each position The second bit (1) is in represents a power of 10. the 2^1 place, so: 1 \times 2^1 = 2. The third bit (0) is in the 2^2 place, so: 0 \times 2^2 = 0.  The fourth bit (1) is in Addition: the 2^3 place, so: 1 \times 2^3 = 8. (carry 1 to the next higher 1 + 1 = 10_2 bit). 3. Add the results: Example: 8 + 0 + 2 + 1 = 11. 101_2 + 110_2 = 1011_2. 4. Therefore, 1011_2 = 11_{10}. Subtraction: Borrowing in binary is similar to Converting Decimal to Binary decimal, but since only 0 and 1 exist, subtraction works by “borrowing” a 1 To convert a decimal number into from a higher place value when the binary, repeatedly divide the decimal subtracted bit is larger. number by 2, recording the quotient Example: and remainder at each step. The 101_2 - 11_2 = 10_2. binary number is formed by reading the remainders from bottom to top. Multiplication and Division: Similar to decimal, but simpler as it Example: Convert 13_{10} to binary: only involves the digits 0 and 1. Example: 1. Divide 13 by 2: 101_2 \times 11_2 = 1111_2. 13 \div 2 = 6 with a remainder of 1. 2. Divide 6 by 2: 6 \div 2 = 3 with a remainder of 0. 3. Divide 3 by 2: 3 \div 2 = 1 with a remainder of 1. 4. Divide 1 by 2: 1 \div 2 = 0 with a remainder of 1. Now, read the remainders from bottom to top: The binary representation of 13_{10} is 1101. Binary Arithmetic Binary arithmetic follows similar rules to decimal arithmetic, but with simpler operations: