Network Devices
Hub -A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets
Switch - Short for port-switching hub, a special type of hub that forwards packets to the appropriate port based on the packet's address. Since switching hubs forward each packet only to the required port, they provide much better performance.
Router - A device that connects any number of LANs. Routers use headers and a forwarding table to determine where packets go, and they use ICMP to communicate with each other and configure the best route between any two hosts. Very little filtering of data is done through routers. Routers do not care about the type of data they handle.
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