Radio Wave Communication

Study Notes

In a star topology, all computers are connected to a central node that controls all activities.
Adding more computers to the network is easy, and the breakdown of computers (except the central node) does not affect the network's functioning.
However, the failure of the central node disables the entire network.

In a mesh topology, every computer is connected to every other computer on the network.
Full mesh topology is expensive to implement, so partial mesh topology is often used, where a computer is connected to a few other computers in the network.

Wired transmission media include cables, which can be used to set up a network.
Twisted pair cable is often used, consisting of a pair of insulated wires twisted together to reduce disturbances in signals.
Twisted pair cabling comes in two varieties: shielded (STP) and unshielded (UTP), with UTP being the most commonly used.
Coaxial cable (coax) is an electrical cable with a conductor at its center, surrounded by a tubular insulating layer.

Metropolitan Area Network (MAN): a computer network that covers a larger area than LAN, connecting two offices in a city, a neighborhood area, etc.
Wide Area Network (WAN): a computer network that spans a wide geographical area, connecting LANs and MANs, often using optical fiber cables, satellite radio links, or microwave radio links.

Various devices are used for setting up a computer network, including wireless routers and adapters.

Radio wave transmission: omnidirectional, easy to generate, and can travel long distances, but subject to interference from motors and other electrical equipment.
Bluetooth technology: used for exchanging data over short distances using radio waves, with low power, short range (30 feet), and medium transmission speed.
WiFi technology: uses radio waves to transmit and receive data, requiring more energy, but enabling signals to go farther (300 feet) with a faster rate of transmission.
WiMAX (Worldwide Interoperability for Microwave Access): similar to WiFi, but operates at higher speeds and can cover greater distances and a greater number of users.