American Fibertek SM9p - Manual (Page 18)

10
X-Ring Application
The switch supports the X-Ring protocol that can help the network system to recovery from
network connection failure within 20ms or less, and make the network system more reliable.
The X-Ring algorithm is similar to spanning tree protocol (STP) algorithm but its recovery time
is faster than STP. The following figure is a sample X-Ring application.
[NOTE]
When the X-Ring function enable, user must disable the RSTP. The X-Ring function and
RSTP function cannot exist at the same time.
In the X-Ring topology, every switch enables X-Ring function and assigns two member
ports in the ring. Only one switch in the X-Ring group would be as a backup switch one of
two member ports backup port then switches are called working switches working ports.
When the network connection fails, the backup port will automatically become a working