Westermo U200 Operator manal - Manual (Page 20)

V4.5
www.westermo.com
U/R/T200 series
- 20 -
Figure 10, FRNT version 0, single ring topology
7.2.2 FRNT version 0, configuration rules
The rules are as follows:
• Port 7 and 8 are FRNT version 0 ports
•
Always connect port 8 to 7, 8 to 7, .. 8 to 7 through the ring
•
Never 7 to 7 or 8 to 8!
• One switch as the network focal point (root)
7.3 FRNT version 1
7.3.1 FRNT version 1 principles
The Fast Re-configuration of Network Topology (FRNT) protocol version 1 is used together
with FRNT version 0 rings, when redundancy between FRNT version 0 rings also is required,
see figure below.
Two FRNT version 0 rings are linked together via a primary and a backup link, where these
two links are originating from two different switches in the same FRNT version 0 ring. These
two switches are both enabled for FRNT version 1 operation. The two links are connected to
two different switches in the second FRNT version 0 ring. These two switches in the second
ring are NOT enabled for FRNT version 1 operation.
Link health packets are sent on both primary and the backup link in order to verify that the
links are ok or not. The primary link is default in packet forwarding state and the backup link
is default in packet blocking state (only link health packets get through). The backup link will
be put in packet forwarding state if the backup link is ok and the:
- primary link is not ok, or
- there is no communication between the primary switch and backup switch