DFM uses the APPC LU 6.2 protocol, defined by Systems Network Architecture (SNA), to communicate with DDM source implementations in an extended enterprise network. The APPC LU 6.2 protocol allows systems in a network to communicate on a peer-to-peer basis.

APPC LU 6.2 support on z/OS systems is provided by APPC/MVS, a part of the base control program (BCP) of z/OS and Virtual Telecommunications Access Method (VTAM®). DFM is conversant in APPC/MVS LU 6.2 protocols and commands. A DDM source implementation is conversant in APPC LU 6.2 protocols and commands.

APPC LU 6.2 on a DDM source system and LU 6.2 on a z/OS system enable conversations to take place between the DDM source and DFM. These conversations carry DDM commands and messages involved in processing remote access to z/OS® data.

For more information about APPC/MVS, see z/OS MVS Planning: APPC/MVS Management.