Glossary

The following terms and phrases are intended to aid the reader in the use of this manual and to clarify terminology as it is utilized in this publication. [Some definitions contained in this Glossary have been extracted or based upon descriptions and entries in Common User Access Panel Design and User Interaction, IBM publication SC26-4351. ]

Access
A Network Center Component designed to control which sessions are allowable within a ACF/VTAM domain.
ACF/VTAM
The Advanced Communications Facility/Virtual Telecommunications Access Method, IBM's System 390 implementation of SNA concepts.
Alias
A name that represents an element (terminal, mode table entry, or class of service) in another network. Commonly used to eliminate confusion between logical units that have the same name in two different SNA networks.
CMS
The Conversational Monitor System, is the interactive portion of IBM's Virtual Machine (VM) operating system.
control vector
Identifies a portion of a defined SNA structure or sub-structure that contains information about an activity occurring within the network.
Cross domain
Describes an action or activity that occurs between two or more VTAM domains (E.G. a "cross domain" session is a session where the PLU and SLU are owned by different copies of ACF/VTAM)
Cross network
Describes an action or activity that occurs between two or more SNA networks (E.G. a "cross network" session is a session where the PLU and SLU are owned by different SNA networks)
CUA
Common User Access, a portion of SAA (Systems Application Architecture) that defines and describes the user interface to the computing system.
DLU
Destination Logical Unit, is a SNA term used to identify the receiving entity or LU in a session or transmission. See also PLU.
domain
The resources (devices, subsystems, etc.) controlled by a single copy of ACF/VTAM.
Group
A list of rule and/or ruleset names that will be considered to be related to each other and identifiable by the group name.
ISTEXCAA
The name for the ACF/VTAM Session Management Exit.
Network Data File
The BSAM accessed disk storage used by The Network Center to keep information across execution on an external storage device.
NETID
The eight character identifier that signifies the name of one or more VTAM domains operating as an individual SNA network.
Network Administrator
The individual or individuals at your installation responsible for the installation and operation of Timeout.
OLU
Originating Logical Unit, is a SNA term used to identify the initiating entity or LU in a session or transmission. See also SLU.
pattern characters
The asterisk "*" or percent sign "%" allow a masking process to be utilized for comparing character strings.
PLU
Primary Logical Unit, is a SNA term used to identify one "side" of a session. The PLU is typically an application subsystem (the Network Center Server operates as a PLU to the Network Center Interface in TSO).
Query
A Network Center Component providing a series of panels for the display and diagnosis of the internal operations of ACF/VTAM.
rule
A set of conditions that, when matched, indicates to Timeout whether to approve or reject a specific session request.
rule set
A grouping of one or more rules.
session
The SNA term for the communications between two LUs (logical units). E.G. A "session" exists between a terminal device and a subsystem.
SDT
Session Directory Table, is the control block maintained by Timeout within the Network Center Server and ACF/VTAM to indicate the session activity between the SLU and PLU for a specific session.
Session Management Exit
The processing point within ACF/VTAM where sessions can be approved or rejected under local installation control. This is the exit point used by Timeout to enforce the rules.
SLU
Secondary Logical Unit, is a SNA term used to identify one "side" of a session. The SLU is typically a terminal device, but may also be a processing program (the Network Center Interface for TSO operates as an SLU).
Subarea
A numeric value that uniquely identifies a hardware processing unit within a VTAM domain. The Subarea value must be unique within a single SNA network.
SSCP
System Services Control Point, the key processing point within a ACF/VTAM domain that manages session initiation and termination.
The Network Center
The name of the NRS product family of ACF/VTAM utility functions. Timeout is a Component of The Network Center.
Timeout
A Network Center Component providing a domain wide inactivity timer for idle terminal sessions.
TSO
The Time Sharing Option, is the interactive portion of IBM's Operating System (OS) operating system (commonly known as MVS, MVS/SP, MVS/XA, or MVS/ESA).
Value Group
a collection of literal values that are referenced within The Network Center's Rule processing as a single element. The first character of a Value Group's name is always an ampersand.
VSCS
VM SNA Console Support, a VTAM application program that operates in the VM environment providing an interface between SNA based devices and the services of CP (VM's Control Program).