F

fill type

A value used in basic conversations that indicates whether programs receive data in the form of logical records or as a specified length of data.

flow

A verb flows from one LU to another.

Format 0 XID

A type of XID that supplies minimal information about a node. These XIDs have a fixed length. They can be used for 3270 and LUA communications, but not for APPC. See also Format 3 XID and XID.

Format 3 XID

A type of XID that supplies more detailed information about a node than a Format 0 XID. These XIDs have a variable length. They can be used for APPC as well as for 3270 and LUA communication. See also Format 0 XID and XID.

full-duplex transmission

Two-way electronic communication that takes place in both directions simultaneously. Contrast with half-duplex transmission.

fully qualified LU name

The two-part network address (network.lu) that uniquely identifies a destination (typically a user) in the network.

Function Management Interface (FMI)

An interface that provides applications with direct access to SNA data flow and information about SNA control flows by means of status messages. It is particularly suited to the requirements of 3270 emulation applications.