An Ethernet hub, active hub, network hub, repeater hub, multiport repeater, or simply hub is a network hardware device for connecting multiple Ethernet devices together and making them act as a single
4-port 10BASE-T Ethernet hub with selectable MDI-X/MDI port
8-port Ethernet hub with one 10BASE2 connector and eight 10BASE-T ports
The physical-layer specifications of the Ethernet family of computer network standards are published by the Institute of Electrical and Electronics Engineers, which defines the electrical or optical p