Computer Networks and Internet Fundamentals

Computer Networks

Types of Networks

• LAN (Local Area Network): connects devices in a limited geographical area, such as a home, office building, or campus
• MAN (Metropolitan Area Network): connects devices in a metropolitan area, such as a city or town
• WAN (Wide Area Network): connects devices over a large geographical area, such as a country or continent
• WLAN (Wireless Local Area Network): connects devices wirelessly in a limited geographical area
• WiMAX (Worldwide Interoperability for Microwave Access): connects devices wirelessly over long distances

Network Topologies

• Physical Topology: the physical layout of devices in a network
• Logical Topology: the way data flows through a network
• Bus Topology: a single cable connects all devices in a linear sequence
• Star Topology: devices connect to a central device, such as a hub or switch
• Ring Topology: devices connect in a circular configuration
• Mesh Topology: each device connects to every other device

Internet

Internet Architecture

• Client-Server Architecture: clients request resources from servers
• Peer-to-Peer Architecture: devices act as both clients and servers
• TCP/IP (Transmission Control Protocol/Internet Protocol): the primary protocol suite used on the internet

Internet Protocols

• IP (Internet Protocol): responsible for routing data packets between networks
• TCP (Transmission Control Protocol): ensures reliable, error-checked data transfer
• UDP (User Datagram Protocol): used for fast, best-effort data transfer
• HTTP (Hypertext Transfer Protocol): used for transferring data over the web
• FTP (File Transfer Protocol): used for transferring files over the internet

Internet Services

• Email: electronic mail services, such as SMTP (Simple Mail Transfer Protocol)
• WWW (World Wide Web): uses HTTP to access and share information over the internet
• FTP (File Transfer Protocol): used for transferring files over the internet
• DNS (Domain Name System): translates domain names to IP addresses