Overview
Computer networking is the practice of interfacing two or more computing devices to share resources and exchange data. It involves a combination of hardware (routers, switches, cables) and software (protocols, drivers) that allow devices to communicate across various distances, from a local area network (LAN) to the global internet.
Core Concepts
- Network Topology: The physical or logical arrangement of a network.
- Bus: All devices share a single communication line.
- Star: All devices connect to a central hub or switch (most common in modern LANs).
- Mesh: Every device is connected to every other device, providing high redundancy.
- Addressing: How devices are identified on a network.
- MAC Address: A unique physical identifier assigned to a network interface card (NIC).
- IP Address: A logical address used for routing data across networks (IPv4 and IPv6).
- Protocols: A standardized set of rules that determine how data is transmitted and received.
- Network Types:
- LAN (Local Area Network): Limited to a small geographic area (e.g., a home or office).
- WAN (Wide Area Network): Covers a large geographic area (e.g., the Internet).
- VPN (Virtual Private Network): An encrypted tunnel over a public network.
Key Components
- NIC (Network Interface Card): The hardware that allows a device to connect to a network.
- Switch: Connects devices within a single LAN and forwards data based on MAC addresses.
- Router: Connects different networks together and forwards data based on IP addresses.
- Firewall: A security system that monitors and controls incoming and outgoing network traffic.
Use Cases
- Distributed Systems: Allowing multiple servers to work together as a single system.
- Cloud Computing: Accessing remote resources over the internet.
- IoT (Internet of Things): Connecting everyday objects to the network for remote monitoring and control.
Gotchas
- Latency vs. Throughput: High throughput (large amount of data) doesn’t always mean low latency (fast response time).
- Packet Loss: Data can be lost during transmission, requiring protocols like TCP to handle retransmissions.
- Security: Networks are inherently open to attacks; encryption (TLS/SSL) and authentication are mandatory for sensitive data.