Services Overview
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FD 100/320Gbps NT and FX NT IHub Services Guide
3HH-11985-AAAA-TQZZA Issue: 13
 
After the MD and MAs are created, the MEP can be created under the SAP in the 
v-VPLS service instances or SAP/SDP in the VPLS service instances or SDP in the 
EPIPE service instances. When creating the MEP, MDs and MAs are associated.
Each MA defined in an MD has a complete view of all of its MEPs. All remote MEPs 
have their IDs listed under the MA configuration. The local MEP is associated with 
the MA under the configuration of the v-VPLS SAP/VPLS SAP or SDP/EPIPE SDP, 
allowing the MA to be aware of all member MEPs in its MEP mesh.
3.11 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 also built on 
Ethernet OAM and often referred to as Ring Automatic Protection Switching 
(R-APS).
Ethernet rings are supported on VPLS SAPs (VPLS, v-VPLS). Eth-ring 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 when possible.
Rings are desired in data networks where the native connectivity is laid out in a ring 
or there is a desire 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. 
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 VLAN (ring data instances) associated with a control instance. Multiple control 
instances allow logically separate rings on the same topology. The Nokia 
implementation supports dot1q encapsulation for data ring instances and the control 
channel. 
3.11.1 Overview of G.8032 operation
R-APS messages that carry the G.8032 protocol are sent on dedicated protocol 
VLAN called ERP VLAN (or Ring Control Instance). In a revertive case: G.8032 
Protocol ensures that one Ring Protection Link (RPL) owner blocks the RPL link. 
RPL owner functionality is introduced in iHUB from R5.0.0.1 release.