| 摘要 |
<p>Stations on a token ring network, such as the IEEE 802.5 Ring Local Area Network (LAN), use a "Secondary Transmit Opportunity" protocol to transmit information onto the ring. A ring station ready to send a buffered message and detecting an idle character immediately following a physical trailer sequence on the ring may insert the message. Simultaneously with transmitting, the station monitors the ring and if a token sequence is detected, checks its priority. If the priority is not higher than the priority of the buffered message, tne station continues the transmission. If the token has a higher priority, the transmission is aborted and the received token is sent. If a start of frame sequence is detected, the station aborts the transmission of the buffered message and forwards the message received from the upstream ring segment.</p> |
