Specifications

2-33
TOKEN RING OVERVIEW
If the frame type is a MAC frame, all stations on the ring act on the state of
ZZZ control bits of the Frame Control field.
There are 25 MAC frames detailed in the standard. For example, 0002
indicates a beacon frame, 0005 is an AM present frame. MAC frames are
used for network operation rather than transfer of higher layer data.
Table 2-1 shows the YYY Control Bit values and functions.
Table 2-1. YYY Control Bit Values and Functions
Major
Vector
ID (Hex)
MAC Frame
Frame
Control
Field (Hex)
Destination
Class
Source
Class
Subvector
(HEX)
00 Response 00 Source class of
received
frame
Station 09
20
01 Beacon 02 Station Station 01
02
0B
03 Claim Token 03 Station Station 02
0B
04 Ring Purge 04 Station Station 02
0B
05 Active
Monitor
Present
05 Station Station 02
0B
06 Standby
Monitor
Present
06 Station Station 02
0B
07 Duplicate
Address Test
01 Station Station None
08 Lobe Test 00 Station Station 26
09 Transmit
Forward
00 Station Config.
Report
Server
27
0B Remove Ring
Station
01 Station Config.
Report
Server
None