KYLAND Technology SICOM3024P, Web Operation Manual

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Advanced Configuration
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detects the status of the ring. When the ring is closed, the two ring ports on the master are
in forwarding and blocking state respectively.

Primary port: indicates the ring port (on the master) whose status is configured as
forwarding forcibly by user when the ring is closed.
Note:
If no primary port is configured on the master, the first port whose link status changes to up
when the ring is closed is in forwarding state. The other ring port is in blocking state.

Slave: A ring can include multiple slaves. Slaves listen to and forward DT-Ring protocol
packets and report fault information to the master.

Backup port: The port for communication between DT rings is called the backup port.

Master backup port: When a ring has multiple backup ports, the backup port with the larger
MAC address is the master backup port. It is in forwarding state.

Slave backup port: When a ring has multiple backup ports, all the backup ports except the
master backup port are slave backup ports. They are in blocking state.

Forwarding state: If a port is in forwarding state, the port can both receive and send data.

Blocking state: If a port is in blocking state, the port can receive and forward only DT-Ring
protocol packets, but not other packets.
6.12.3 Implementation
DT-Ring-Port Implementation
The forwarding port on the master periodically sends DT-Ring protocol packets to detect ring
status. If the blocking port of the master receives the packets, the ring is closed; otherwise,
the ring is open.
Working process of switch A, Switch B, Switch C, and Switch D:
1. Configure Switch A as the master and the other switches as slaves.
2. Ring port 1 on the master is in forwarding state while ring port 2 is in blocking state. Both
two ports on the slave are in forwarding state.
3. If link CD is faulty, as shown in the following figure:
a) When link CD is faulty, port 6 and port 7 on the slave are in blocking state. Port 2 on the