This reports the sub-port name associated with this remote MEP, identifying the specific logical sub-interface (such as a PBB-TE service or MPLS VC endpoint) on the far end that this remote peer belongs to, rather than just a bare physical port. An admin uses this to correlate a remote MEP entry with the exact logical service instance it represents on the remote device, particularly useful when a single physical port hosts multiple distinct sub-port services. For example, cienaCesCfmRemoteMEPSubPortName reading 'PBT-Tunnel-42' tells the admin this remote MEP specifically belongs to that named PBB-TE tunnel sub-port rather than some other service sharing the same remote physical port.