Repeaters extend the communication distance. The maximum number of nodes has been increased. Each network segment can use different communication rates. Improved reliability. When the network fails, it generally only affects individual network segments. The Internet performance is improved.

The repeater can connect the cables of two LANs, re-time and regenerate the digital signals on the cables, and then send them out. These functions are typical of the physical layer, the first layer in the OSI model. The function of the repeater is to increase the coverage area of the LAN. For example, the Ethernet standard stipulates that the maximum length of a single section of signal transmission cable is 500 meters. However, after connecting five sections of cables with the repeater, the maximum length of the signal transmission cable in the Ethernet can reach 2500 meters. Some brands of repeaters can connect cable segments with different physical media, such as thin coaxial cables and optical cables.