Users Guide

Ethernet Ring Protection 1001
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Ethernet Ring Protection
Dell EMC Networking N1500, N2200 Series Switches
Ethernet Ring Protection (ERP) is a highly reliable and stable protection
switching mechanism Ethernet layer network rings. Ethernet rings allow a
wide-range of economical multipoint connectivity topologies due to their
reduced number of links. The Ethernet Ring Protection feature is based on
the ITU-T G.8032 (08/15), Corrigendum 1 (08/17) standard. Ethernet Ring
Protection Switching defines Ring Automatic Protection Switching (R-APS)
Protocol Data Units (PDUs) and protection switching mechanisms. The
Ethernet Ring Protection feature is supported on all Ethernet port types on
the N1500/N2200 Series platforms.
Ethernet Ring Protection does not support Non-Stop Forwarding. Stack
failover is destructive to the ring, even when operating on stack units that are
not rebooted during the stack failover.
Each node in the ring connects to the ring via two ports, known as ring links.
These are often referred to as the East and West ring links respectively. Each
ring link is bounded by two neighbors (Ethernet ring nodes). The minimum
number of ring nodes in a ring is two. At any time, traffic may flow through all
but one of the ring links which ensures a loop free ring. This particular link is
known as the Ring Protection Link (RPL). Under normal conditions, the RPL
is blocked (not used for data traffic). One end of the RPL is designated as the
owner, and the other end of the link is designated as the neighbor.
Ring links may be configured as part of a port-channel or M-LAG and may
participate in an L2 (spanning-tree network) or an L3 (routed) network.