MEF 6.3 is a specification document developed by the STA of the MEF.
"This document defines three Subscriber Ethernet Service constructs called Subscriber Ethernet Service Types and six Subscriber Ethernet Services with Service Attribute values as specified in MEF 10.4, “Subscriber Ethernet Services Attributes”  and in MEF 45.1, “Layer 2 Control Protocols in Ethernet Services” . These Subscriber Ethernet Service Types are used to create Point-to-Point, Multipoint-to-Multipoint, and Rooted-Multipoint Ethernet Services that are either Port or VLAN based. This document supersedes and replaces MEF 6.2, “EVC Ethernet Services Definitions – Phase 3”.
In addition, an informative appendix is provided showing examples of some of the defined Subscriber Ethernet Services. This document also provides guidance on backwards compatibility to a Subscriber Ethernet Service as defined in MEF 6.2, “EVC Ethernet Services Definitions – Phase 3."