Cisco ASR 920 series Configuration Guide Ethernet Router

Information About Configuring Ethernet CFM in a Service
Provider Network
Ethernet CFM
Ethernet CFM is an end-to-end per-service-instance Ethernet layer OAM protocol that includes proactive
connectivity monitoring, fault verification, and fault isolation. End to end can be PE to PE or CE to CE. A
service can be identified as a service provider VLAN (S-VLAN) or an EVC service.
Being an end-to-end technology is the distinction between CFM and other metro-Ethernet OAM protocols.
For example, MPLS, ATM, and SONET OAM help in debugging Ethernet wires but are not always end-to-end.
802.3ah OAM is a single-hop and per-physical-wire protocol. It is not end to end or service aware.
Troubleshooting carrier networks offering Ethernet Layer 2 services is challenging. Customers contract with
service providers for end-to-end Ethernet service and service providers may subcontract with operators to
provide equipment and networks. Compared to enterprise networks, where Ethernet traditionally has been
implemented, these constituent networks belong to distinct organizations or departments, are substantially
larger and more complex, and have a wider user base. Ethernet CFM provides a competitive advantage to
service providers for which the operational management of link uptime and timeliness in isolating and
responding to failures is crucial to daily operations.
Benefits of Ethernet CFM
•
End-to-end service-level OAM technology
•
Reduced operating expense for service provider Ethernet networks
•
Competitive advantage for service providers
•
Supports both distribution and access network environments with the outward facing MEPs enhancement
Customer Service Instance
A customer service instance is an Ethernet virtual connection (EVC), which is identified by an S-VLAN within
an Ethernet island, and is identified by a globally unique service ID. A customer service instance can be
point-to-point or multipoint-to-multipoint. The figure below shows two customer service instances. Service
Instance Green is point to point; Service Instance Blue is multipoint to multipoint.
Carrier Ethernet Configuration Guide (Cisco ASR 920 Series)
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Configuring Ethernet Connectivity Fault Management in a Service Provider Network
Information About Configuring Ethernet CFM in a Service Provider Network

Cisco ASR 920 series Specifications

General

Brand	Cisco
Model	ASR 920 series
Category	Network Router
Language	English