What physical devices are required for a token ring network?
Token ring connectivity requires three separate physical entities; a Multistation Access Unit (MAU), a token ring lobe cable, and a token ring adapter card. A Multistation Access Unit (MAU or MSAU) is a hub-like device that connects to all token ring stations. Although the token ring stations are attached to the MAU in a physical star configuration, a true ring is maintained inside the MAU. Unlike an Ethernet hub, a MAU consists of physical or electronic relays which keep each station in a loopback state until a voltage is sent from the station to the MAU. Since this voltage does not affect data communications, it is referred to as a ‘phantom’ voltage. Once this phantom voltage is received by the MAU, a relay is activated that inserts the token ring station onto the ring. MAUs are connected together with Ring In/Ring Out (RI/RO) cables. To maintain a true ring, both the RI and the RO ports must be connected from one MAU to the other. A token ring lobe cable connects the token ring stat
