3.5 Fundamentals of Computer Networks

• Computer networks are used to connect devices such as personal computers (PC), laptops, smartphones, tablets, printers, scanners, cameras, and other peripheral equipment.
• Networking hardware includes routers, switches, hubs, modems, access points, firewalls, bridges, repeaters, and gateways.
• The Internet is the largest computer network, connecting millions of computers worldwide.
• Routers forward packets between different network segments based on their destination addresses.
• Intranets are private networks within an organization or institution that can be accessed only by authorized users.
• Switches forward frames within the same segment using MAC addresses.
• Hubs replicate incoming signals and send them out all ports.
• Extranets allow limited access from outside organizations to internal resources.
• Switches forward frames within a single segment using MAC addresses.
• Modems convert digital data into analog signals for transmission over telephone lines or vice versa.
• Wide Area Networks (WAN) cover large geographic areas and use public telecommunication lines like telephone cables, fiber optic cables, microwave links, satellite communication, etc.
• Hubs retransmit signals from one port to all ports.
• Hubs receive incoming signals from multiple sources and retransmit them to all connected devices.
• Extranets allow selected external parties to access specific parts of an intranet.
• Wide area networks (WAN) cover large geographic areas and use technologies like leased lines, satellite links, and wireless connections.
• Modems convert digital data into analog signals for transmission over phone lines.
• Modems convert digital data into analog signals for transmission over telephone lines.
• WANs (wide area networks) connect geographically dispersed locations over long distances.
• Access points allow wireless devices to connect to wired networks.
• WANs (wide area networks) connect geographically dispersed locations over long distances.
• Access Points allow wireless devices to connect to wired networks.
• Metropolitan Area Networks (MAN) serve a city-wide region and may include multiple WANs.
• Repeaters amplify weak signals and regenerate them, but do not change their content.
• Repeaters amplify weak signals and regenerate them, but do not change their content.
• LANs (local area networks) cover smaller areas such as buildings or campuses.
• LANs (local area networks) cover smaller areas such as buildings or campuses.
• Metropolitan Area Networks (MAN) serve a city-wide region and may include multiple WANs.
• WAN (wide area network) is a computer network covering a large geographic area, such as a country or continent.
• WAN (wide area network) is a computer network covering a large geographic area, such as a country or continent.
• Firewalls protect networks from unauthorized access and block unwanted traffic.
• Firewalls protect networks from unauthorized access and block unwanted traffic.
• Bridges connect two segments with different network technologies (e.g., Ethernet and Token Ring).
• Bridges connect two segments with different network technologies (e.g., Ethernet and Token Ring).
• Metropolitan Area Networks (MANs) span cities or metropolitan areas.
• Metropolitan Area Networks (MANs) span cities or metropolitan areas.
• LAN (local area network) is a computer network covering a small geographic area, such as a building or campus.
• LAN (local area network) is a computer network covering a small geographic area, such as a building or campus.
• Metropolitan Area Networks (MAN) are used by businesses located close together in an urban area.
• Metropolitan Area Networks (MAN) are used by businesses located close together in an urban area.
• Routers interconnect multiple networks at different layers of the OSI model.