User Manual

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Users Manual of XGS-6350-24X4C
Chapter 26. EAPS Configuration
Introduction of Fast Ethernet Ring Protection
26.1
26.1.1 Overview
The Ethernet ring protection protocol is a special type of link-layer protocol specially designed for constructing
the ring Ethernet topology. The Ethernet protection protocol can shut down one link in a complete ring
topology, preventing the data loop from forming the broadcast storm. If a link is broken, the protocol
immediately resumes the link that is previously shut down. In this way, the nodes among the ring network can
communicate with each other.
The ring protection protocol and STP are both used for topology control on the link layer. STP is suitable for all
kinds of complicated networks, which transmits the change of network topology hop by hop. The ring
protection protocol is used for ring topology and adopts the pervasion mechanism to transmit the change of
network topology. Therefore, the convergence of the ring protection protocol in the ring network is better than
STP. In a sound network, the ring protection protocol can resume network communication within less than
50ms.
Remark:
EAPS supports to set a switch to be a node of multiple physical ring to construct complicated topology.
26.1.2 Related Concepts of Fast Ether-Ring Protection
Figure 1.1 EAPS Ethernet ring
26.1.2.1 Roles of Ring’s Nodes
Each switch on an Ethernet ring is a ring node. The ring nodes are classified into master nodes and transit
nodes. Only one switch on the Ethernet ring can serve as a mere master node and other switches are worked