Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Software Configuration Guide, Release 12.2(33)MRB

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Chapter 4 Configuring the Cisco MWR 2941 Router Using the CLI

Configuration Sequence

Figure 4-3 Ethernet CFM Maintenance Domain Hierarchy

Maintenance Point

A maintenance point is a demarcation point on an interface (port) that participates in CFM within a

maintenance domain. Maintenance points on device ports act as filters that confine CFM frames within

the bounds of a domain by dropping frames that do not belong to the correct level. Maintenance points

must be explicitly configured on Cisco devices. Two classes of maintenance points exist, MEPs and

MIPs.

Maintenance Endpoints (MEPs)

MEPs have the following characteristics:

• Per maintenance domain (level) and service (S-VLAN or EVC)

• At the edge of a domain, define the domain boundary

• Confine CFM messages within the bounds of a maintenance domain,

• Can proactively transmit CFM continuity check messages (CCMs)

• Can transmit traceroute and loopback messages at administrator request

Inward Facing MEPs

Inward facing means the MEP communicates through the Bridge Relay function and uses the

Bridge-Brain MAC address. An inward facing MEP performs the following functions:

• Sends and receives CFM frames at its level through the relay function, not via the wire connected

to the port on which the MEP is configured.

• Drops all CFM frames at its level (or lower level) that come from the direction of the wire.

Operator

Domain

Provider

Domain

Customer

Domain

PE PE

PEPE

Scenario A:

Touching Domains OK

Scenario B:

Intersecting Domains Not

Allowed

Scenario C:

Nested Domains OK

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