Applicable to end systems concerned with operating in the Open Systems Interconnection (OSI) environment. Specifies a combination of OSI base standards that collectively provide the connection-mode Transport Service using the connectionsless-mode Network Service. Applicable to the provision of the connection-mode Transport Service in end systems attached to an FDDI LAN subnetwork from which the standardized connectionless-mode Network Service can be made available. Defines the profile TA54.