Date Added: Apr 2010
In token-passing ring local area networks, the shared transmission medium is closed and it has a formation of loop. The information transmission is unidirectional. Access to the transmission medium is regulated with the help of a token-small packet that consists of about eight bits. All stations are attached to the transmission medium using active interfaces that can modify the information passing through it. When the station has some information to transmit, its interface monitors the transmission medium and searches for immediately a free token. As it detects a free token it captures the token, changes the status of the token from idle to busy. Subsequently the data is transmitted immediately.