Antaira Technologies - Industrial Ethernet Switches
LMP-0800G-24 Series User Manual V1.0
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Ethernet Ring Protection Switching (ERPS)
, defined in ITU-T G8032, implements a protection
switching mechanism for Ethernet traffic in a ring topology. By performing the ERPS function,
potential loops in a network can be avoided by blocking traffic to flow to the ring protection link (RPL)
to protect the entire Ethernet ring.
In a network wit
h ring topology that runs ERPS, only one switch is assigned as an “owner” that is
responsible for blocking traffic in RPL so as to avoid loops. The switch adjacent to the RPL owner is
called the RPL “neighbor” node that is responsible for blocking its end of the RPL under normal
condition. Other participating switches adjacent to the RPL owner or neighbor in a ring are
members or RPL next-neighbor nodes to this topology and normally forward receive traffic.
ERPS, like STP, provides a loop-free network by using polling packets to detect faults. When a fault
occurs, ERPS heals itself by sending traffic over a protected reverse path less than 50ms and
recover quickly to forward traffic. Because of this fault detection mechanism, the network broadcast
storm problem could be avoided as well.
5.5.1 ERPS Status
Below is the REPS LED information on the front Panel
Terms
Value Description
MASTER
ON(Green):
If one of ERPS ports is set to RPL “Owner”.
OFF(Gray)
: No port is set to RPL “Owner”
RING
ON(Green)
: ERPS works well.
ON(Flashing)
: The ring is open, one of ERPS node link failed or link down or
ERPS is misconfigured.
OFF(Gray)
: ERPS is disabled.
Below,
Figure 5.21,
shows the network redundancy ring status with the Ethernet Ring Protection
Switch (ERPS) protocol.
Figure 5.21
– Redundant Ring Network – ERPS Status
