What CFM entity is created at the edge (entry/exit) points of the service being monitored?

The correct answer is Maintenance End Point (MEP). MEPs are critical components in the context of Ethernet networks, particularly when monitoring and managing service quality and network performance through OAM (Operations, Administration, and Maintenance) functions.

A Maintenance End Point is specifically established at the boundaries of a service - meaning at the entry and exit points of the service being monitored. This allows for effective monitoring and management of end-to-end service performance, as MEPs can generate continuity check messages and perform fault detection, which are fundamental for ensuring the reliability of the service.

In contrast, a Maintenance Point (MP) is less specific and can refer to any point within a Maintenance Domain, while Link Trace Points (LTP) are used for tracing the path of Ethernet frames in a network but are not necessarily tied to the service's endpoints. Finally, a Service Discovery Point (SDP) relates to service discovery mechanisms and does not directly pertain to the performance monitoring focus associated with MEPs. Thus, MEPs are essential for effectively tracking and managing the health of a service across its lifecycle in the carrier Ethernet context.