Networking

Computer Networks

Computer networks are interconnected systems that facilitate the exchange of data and resources among computers and other devices. These networks can be as small as a local area network (LAN) within a single building or as vast as the global internet. Here are some key aspects of computer networks:

  1. Components of a Computer Network:
    • Nodes: Devices connected to the network, such as computers, servers, routers, and switches.
    • Links: The physical or wireless connections that enable data transmission between nodes.
  2. Types of Computer Networks:
    • LAN (Local Area Network): A network that covers a small geographic area, typically within a single building or campus.
    • WAN (Wide Area Network): Spans a larger geographical area, connecting multiple LANs across cities or countries.
    • MAN (Metropolitan Area Network): Covers a larger geographic area than a LAN but is smaller than a WAN, often connecting multiple buildings within a city.
    • PAN (Personal Area Network): A network for personal devices within the immediate surroundings of an individual, like Bluetooth connections.
  3. Network Topologies:
    • Bus Topology: All nodes share a single communication line.
    • Star Topology: All nodes are connected to a central hub or switch.
    • Ring Topology: Nodes are connected in a circular fashion.
    • Mesh Topology: Nodes are interconnected, providing multiple paths for data transmission.
  4. Networking Devices:
    • Router: Connects different networks, directing data between them.
    • Switch: Connects devices within the same network, forwarding data based on MAC addresses.
    • Hub: Basic networking device that connects devices but operates at the physical layer.
    • Access Point: Enables wireless devices to connect to a wired network.
  5. Communication Protocols:
    • TCP/IP (Transmission Control Protocol/Internet Protocol): The foundational suite of protocols for internet communication.
    • UDP (User Datagram Protocol): Connectionless protocol often used for real-time applications.
    • HTTP/HTTPS (Hypertext Transfer Protocol/Secure): Protocols for web communication.
    • FTP (File Transfer Protocol): Used for transferring files between computers.
  6. Networking Models:
    • OSI Model (Open Systems Interconnection): Divides network communication into seven layers, from physical transmission to application.
    • TCP/IP Model: A simplified model closely aligned with the OSI model, commonly used in practice.
  7. Network Security:
    • Firewalls: Protective barriers that filter and monitor network traffic.
    • Encryption: Securing data by converting it into a code.
    • Intrusion Detection and Prevention Systems (IDPS): Monitor network or system activities for malicious actions.
  8. Challenges in Networking:
    • Bandwidth: The capacity of a network to transmit data.
    • Latency: The time delay between the sender’s transmission and the receiver’s reception.
    • Reliability: Ensuring the network operates consistently without failures.