Specifications

2-25
TOKEN RING OVERVIEW
Request Ring Station State (RQ_STATE)
This frame is transmitted by any of the management servers to a station. It
is a request for information of the state of the station.
Response (RSP)
This frame is transmitted by any station to acknowledge receiving, or to
report errors in a MAC frame.
FRAME TYPES
Bit sequences are transmitted onto the ring in clearly defined groups
known as frames. Most frames carry fields of information that are
common to all frame types. The frame types are as follows:
• Fill Sequence
• Abort Delimiter
• Token
• LLC data frame
• SMT data frame
• MAC management frame
Fill Sequence
The following defines the Fill Sequence:
• Generated by the transmitting station before and after frames, tokens,
or aborts.
• Not frames by starting or ending fields.
• Any combination of ones and zeros to expiration of the Token Holding
Timer.
• Avoids quiet line, which is defined as an open ring, during normal
operation.