Tech moves fast! Stay ahead of the curve with Techopedia!
Join nearly 200,000 subscribers who receive actionable tech insights from Techopedia.
A repeating hub is an active network communication device that has multiple ports and combines the functionalities of a signal repeater and a network hub. A repeating hub regenerates and retransmits all incoming signals across all the ports except the port that originated the signal. A repeating hub is normally used to extend the operational range limitations of physical media such as twisted pair cables. The repeating hub works at the physical layer of the OSI reference model.
A repeating hub is a mixture of two network devices: a repeater and a hub. A repeater is an active device designed to regenerate and rebroadcast an electric signal, usually to overcome the inevitable power (signal strength) losses incurred as that signal propagates along a cable. Repeaters are required in order to cover long distances without losing signal strength. Repeaters regenerate every signal as received by the devices, which includes both a signal and noise. Intelligent repeaters overcome this problem by disseminating the induced noise from the original signal.
A hub is a networking device used to interconnect multiple network nodes for communication over twisted-pair or fiber-optic cables. A hub is a nonmanaged device that transmits incoming data packets to all its ports except the incoming port. It also acts in collision detection by forwarding jam signals to all the ports if it detects a collision over the network. The hub, like the repeater, works on the physical layer of the OSI reference model.
Repeating hubs not only improve system performance by boosting signals’ voltage levels, but they also eliminate the need for termination resistors in the network. With a hub-based system, each and every cable terminates at either a data terminal equipment (DTE) or data circuit-terminating equipment (DCE) device.
Repeating hubs have one collision domain. As they boost and rebroadcast signals received by their ports, their presence does not mitigate collisions between transmitting devices. A collision happening in one portion of the network appears to happen in all portions of the network. This problem is solved by transmitting jamming signal to all ports. This collision mitigation technique manages collision but also degrades network performance by repeated broadcasts.
Another disadvantage of repeating hubs is that they are unmanaged devices. They cannot be configured to manage performance parameters, delivery paths and network security.