The token bus LAN is a local area network (LAN) constructed in bus topology, which is standardized in media access according to IEEE 802.4.
The access procedure is deterministic according to the selection principle, whereby each station is authorized to transmit for a limited time when it possesses the token. For each station, the maximum time until the next media access can be determined. In the token bus protocol, a logical ring is implemented on a physical bus topology.
#o The logical ring is created by each station knowing the address of its successor station (address chaining). The token bus procedure is standardized for baseband and broadband technology as well as for the associated coaxial media. For baseband transmissions, transmission rates of 1 Mbit/s or 5 Mbit/s and 10 Mbit/s with phase-coherent frequency shift ke ying are available. For broadband transmissions, 1 Mbit/s, 5 Mbit/s and 10 Mbit/s are available at different frequency ranges. The protocol allows priority classing.