Echo messaging for operation, administration, and management of a
service-based distribution path and associated services are disclosed.
Service-based distribution paths or transport tunnels include services
mapped or bound to a path associated with the transport tunnel. Echo
messaging provides OAM capabilities to monitor the operational state of a
service-based distribution path, including determining configuration,
connectivity, and other characteristics of the path and associated
services that transport data. OAM functions provided by echo messaging
enable OAM functions despite service volume along a core network, path or
set of paths.