Note: Among ports forming the ring network, the Tx mode of at least one
port shall be enabled.
When the loop protection function is enabled to form a ring network, devices
without the management function can be added into the ring network.
When a ring network is formed, blocked ports are located on the devices
where loop protection is enabled.
6.9
ERPS-E config
Function Brief
Ethernet Ring Protection Switching (ERPS) is an Ethernet multi-ring
protection technology defined in ITU-TG.8032. Aiming to improve network
performance and security, ERPS is an Ethernet ring technology that
becomes an important redundancy protection measure on the L2 network.
On the L2 network, STP is often used to ensure network reliability,
and the loop protection protocol may also be used. STP is a standard ring
protection protocol developed by IEEE, and has been widely used. In
practice, application of STP is restricted by the network size, and the
convergence time is affected by the network topology. The convergence
time of STP is generally several seconds, or longer if the network diameter
is large. The use of RSTP/MSTP can reduce the convergence time to
several milliseconds, but still cannot meet the requirements of services
(such as 3G and NGN voice services) that require a high Quality of Service
(QoS). ERPS emerges to further reduce the convergence time and eliminate
the impact caused by the network size.
ERPS is a link layer protocol dedicated for the Ethernet ring. It can
prevent broadcast storms caused by data loops in an Ethernet ring. When a
link on the Ethernet ring is disconnected, the backup link can be quickly
enabled to recover communication between nodes on the ring network.
Compared with STP, ERPS features a fast topology convergence speed
(less than 20 ms) and the convergence time that is independent of the
