SNA Terminology

Abbrev.

Expansion

Definition

APPC

Advanced Program-to-Program

An SNA protocol that's used to communicate between peer-to-peer systems.

Communications

APPN

Advanced Peer-to-Peer Networking

An IBM Network architecture that allows computers to communicate as peers .

FDDI

Fiber Distributed Data Interface

A high speed type of network connection that uses optical fiber cabling.

ISDN

Integrated Services Digital Network

A switched digital connection that can be used for high speed remote connections.

LEN

Low Entry Networking

A PU 2.1 APPN node that can use the routing services provided by another APPN node.

LU

Logical Unit

An SNA component that provides system access.

LU 0

Logical Unit protocol that is used in banking environments.

LU 1

Logical Unit that is used for multi-device SNA data stream printers.

LU 2

Logical Unit that is used for 3270 display devices.

LU 3

Logical Unit that is used for single-device 3270 data stream printers.

LU 6.2

Logical Unit that is used for peer-to-peer communications.

PU

Physical Unit

An SNA component that designates the type of device.

PU 2.0

An SNA device that communicates to a host system as a peripheral node.

PU 2.1

An SNA device that is an extension of the PU 2.0 node support. A PU 2.1 node

communicates as a peer system.

SAA

Systems Application Architecture

An IBM standard that described standard system access methods.

SDLC

Synchronous Data Link Control

An SNA protocol that is used for remote connections between IBM mainframe and

midrange computers.

SNA

Systems Network Architecture

A suite of communications protocols that is used for communications to IBM mainframe

and midrange computers.

Shared

A feature of CA/400 that allows PC to use an AS/400's disk storage.

Twinaxial

A cable type used for direct connections to the AS/400.

3270

A type of display device that is usually used to connect to an IBM mainframe.

5250

A type of display device that is used to connect to an IBM midrange computer.