Brocade Multi-Service IronWare Administration Guide (Supporting R05.6.00) - Manual (Page 165)

Multi-Service IronWare Administration Guide 147
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Mechanisms of Ethernet IEEE 802.1ag OAM
6
IEEE 802.1ag provides hierarchical network management
Maintenance Domain (MD)
A Maintenance domain is part of a network controlled by a single operator. In Figure 7 , we have
customer domain, provider domain and operator domain.
Maintenance Domain level (MD level)
The MD levels are carried on all CFM frames to identify different domains.For example, in Figure 7 ,
some bridges belong to multiple domains. Each domain associates a MD level.
• Customer Level: 5-7
• Provider Level: 3-4
• Operator Level: 0-2
Maintenance Association (MA)
Every MD can be further divided into smaller networks having multiple Maintenance End Points
(MEP). Usually MA is associated with a service instances (for example a VLAN or a VPLS).
Maintenance End Point (MEP)
MEP is located on the edge of an MA. It defines the endpoint of the MA. Each MEP has unique ID
(MEPID) within MA. The connectivity in a MA is defined as connectivity between MEPs. MEP
generates Continuity Check Message and multicasts to all other MEPs in same MA to verify the
connectivity.
Maintenance Intermediate Point (MIP)
MIP is located within a MA. It responds to Loopback and Linktrace messages for Fault isolation.
Mechanisms of Ethernet IEEE 802.1ag OAM
Mechanisms supported by IEEE 802.1ag include Connectivity Check (CC), Loopback, and Link
trace. Connectivity Fault Management allows for end-to-end fault management that is generally
reactive (through Loopback and Link trace messages) and connectivity verification that is proactive
(through Connectivity Check messages).
Fault detection (continuity check message)
The Continuity Check Message (CCM) provides a means to detect hard and soft faults such as
software failure, memory corruption, or misconfiguration. The failure detection is achieved by each
Maintenance End Point (MEP) transmitting a CCM periodically within its associated Service
Instance.