IBM Terminology

 100BASE-T
The IEEE 802.3 Ethernet standard that supports a transmission rate of 100 Mbps using two twisted-pair wires.

 1024-byte format
A format for diskette 2D diskettes with 1024 bytes per sector and 8 sectors per track.

 10BASE-T
The IEEE 802.3 Ethernet standard that supports a transmission rate of 10 Mbps using two twisted-pair wires.

 128-byte format
A format for diskette 1 diskettes with 128 bytes per sector and 26 sectors per track.

 16-bit code set
See double-byte character set.

 16MB boundary
A notional boundary in virtual storage. Addresses below the 16MB boundary can be accessed by 24-bit or 31-bit addressing. Addresses on or above the 16MB boundary can be accessed only by 31-bit addressing. The numerical value of 16MB is 2 to the power of 24, 16 777 216

 16 megabyte line
See 16MB boundary.

 16-pack
See disk 16 pack.

 1980 X.25 call
A call that conforms to the 1980 X.25 protocol specifications.

 1984 X.25 call
A call that conforms to the 1984 X.25 protocol specifications.

 1988 X.25 call
A call that conforms to the 1988 X.25 protocol specifications.

 1A keyboard
A keyboard for non-programmable workstations that is associated mostly with IBM terminals that are attached to IBM controllers such as the 3174, 3274, and 5294. It has 104 keys in all versions except Katakana, which has 106 keys. A numeric key pad option adds another 18 keys to the keyboard. See also G keyboard.

 1-safe algorithm
A method of transaction processing where transactions are committed on the primary server and then propagated to the secondary server afterward. If the primary server fails before it sends the transactions to the secondary server, the transactions will not be visible on the secondary server. See also 2-safe algorithm.

 256-byte format
A format for diskette 2D diskettes with 256 bytes per sector and 26 sectors per track.

 2 B-channel transfer feature
See Integrated Services Digital Network two B-channel transfer.

 2PKDP
See Two-Party Key Distribution Protocol.

 2-safe algorithm
A method of transaction processing where transactions are not considered commiitted on the primary server until the transaction is confirmed committed on the secondary server. All updates to the data are applied to both copies synchronously. The disadvantage of a 2-safe system is that if the secondary server fails, the primary server stops accepting transactions. See also 1-safe algorithm.

 3270 attention field
A field on a display screen that contains a null, a space, or an ampersand in the first position. The field can be selected using the Cursor Select key, which causes data to be sent to the host system.

 3270 device emulation
The i5/OS support that allows a system to appear as a 3274 Control Unit in a BSC multipoint network or an SNA network.

 3270 display emulation
The function of i5/OS 3270 device emulation support that converts 3270 data streams intended for a 3278 display station into data streams that can be recognized by a display station attached to the system.

 3270 emulation
The use of software that enables a client to emulate an IBM 3270 display station or printer, and to use the functions of an IBM host system.

 3270 host application
An application on the IBM System/370, System/390, or iSeries that interacts with terminals supporting the 3270 data stream.

 3270 Host Connection Program (HCON)
A program that allows a system unit to emulate a workstation or printer attached to a System/370 host.

 3270 pass-through mode
A mode that lets a program running in a shell environment send and receive a data stream or issue TSO/E commands.

 3270 printer emulation
The function of i5/OS 3270 device emulation support that converts 3270, DSC, and SCS data streams intended for a 328X printer into data streams that can be recognized by a printer attached to the system.

 3270 server
A function of WebSphere Voice Response that provides a software interface between DirectTalk and IBM System/370, System/390, or iSeries architecture business applications that interact with terminals supporting the 3270 data stream. See also custom server.

 32-name mode
A mode of running the storage management subsystem (SMS) in which up to 32 names, representing systems, system groups, or both, are supported in the SMS configuration. When running in this mode, the system can share source control data sets (SCDSs), active control data sets (ACDSs), and communications data sets (COMMDSs) only with other systems running in 32-name mode. See also compatibility mode.

 370 mode
In CICS/VSE, An operation mode of the supervisor (generated with MODE=370) of a VSE system. Such a supervisor supports multiple virtual address spaces and requires a processor of the System/370 and /390 architecture.

 3DES
See Triple Data Encryption Algorithm.

 3G
See third generation.

 3GL
See third-generation language.

 3-state check box
A square box with associated text that represents a choice. Unlike a regular check box, which has only two states (selected and deselected), a 3-state check box has three states (selected, deselected, and unavailable). The unavailable state is displayed as a halftone and denotes that the 3-state check box cannot be selected.

 512-byte format
A format for diskette 1 diskettes with 512 bytes per sector and 8 sectors per track.

 5250 display
Any display device that uses the 5250 data stream. See also Programming Development Manager.

 5250 emulation
Any one of many licensed programs that allow a personal computer to perform like a 5250 display station or printer and to use the functions of an IBM i operating system.

 5290 display
Any display station from the 5290 Display System.

 5ESS
1. A Lucent Technologies switch.
2. The ISDN protocol implemented on the 5ESS switch, providing 23 B-channels and a D-channel over a T1 trunk.

 8B/10B encoding
An algorithm for encoding data for transmission in which each 8-bit data byte is converted to a 10-bit transmission character. 8B/10B encoding supports continuous transmission with a balanced number of ones and zeros in the code stream and detects single bit transmission errors.

 8-bit character
A single-byte character that consists of eight bits, which means that the code point is in the range 128 through 255. See also single-byte character.

 8-bit clean
Pertaining to software that can process character data that contains 8-bit characters. The operating system or the database server reads the eighth bit as part of the code value.

 8-name mode
See compatibility mode.

 8-pack
See disk eight pack.