G.8032 Ethernet Ring Protection Switching - Alcatel-Lucent 7210 SAS M Service Manual

Services

G.8032 Ethernet Ring Protection Switching

Ethernet ring protection switching offers ITU-T G.8032 specification compliance to achieve
resiliency for Ethernet Layer 2 networks. Similar to G.8031 linear protection (also called
Automatic Protection Switching (APS)), G.8032 (Eth-ring) is built on Ethernet OAM and often
referred to as Ring Automatic Protection Switching (R-APS).
Eth-rings are supported on VPLS SAPs. VPLS services supporting Rings SAPs can connect to
other rings and Ethernet service using VPLS, and R-VPLS SAPs. Eth-rings enables rings for core
network or access network resiliency. A single point of interconnection to other services is
supported. The Eth-ring service is a VLAN service providing protection for ring topologies and
the ability to interact with other protection mechanisms for overall service protection. This ensures
failures detected by Eth-ring only result in R-APS switchover when the lower layer cannot recover
and that higher layers are isolated from the failure.
Rings are preferred in data networks where the native connectivity is laid out in a ring or there is a
requirement for simple resilient LAN services. Due to the symmetry and the simple topology,
rings are viewed a good solution for access and core networks where resilient LANS are required.
The Alcatel-lucent implementation can be used for interconnecting access rings and to provide
traffic engineered backbone rings. The 7210 SAS implementation of G.8032 supports dual inter-
connected rings with sub-rings.
Eth-rings use one VID per control per ring instance and use one (typically) or multiple VIDs for
data instances per control instance. A dedicated control VLAN (ERP VLAN) is used to run the
protocol on the control VID. G.8032 controls the active state for the data VLANs (ring data
instances) associated with a control instance. Multiple control instances allow logically separate
rings on the same topology. The Alcatel-lucent implementation supports dot1q, and qinq
encapsulation for data ring instances. The control channel supports dot1q and qinq encapsulation.
7210 SAS M Services Guide Page 45