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Day 21. Networking Fundamentals > LANs, WANs, and WLANs
LANs, WANs, and WLANs
A network is a group of PCs and devices that serve different functions.
LANs
In a local-area network (LAN), devices are close by (within a building, campus, or house) and include use of upper-layer protocols. LANs are end-user oriented.
WANs
Wide-area networks (WAN) are full of Layer 2 and 3 devices (switches and routers) and contain few actual computers. WANs connect LANs to each other and can extend enormous distances around the world, and literally beyond into space, using wireless technologies.
WLANs
Wireless LANs (WLAN) are commonly known as WiFi. These “spots” allow portable devices such as PDAs, phones, laptops, heart monitors, alarm systems, and others to connect to each other and to the Internet. The physical layer of a WLAN is the antennas and radio signals.
