Introduction to Tandem X.25 Capabilities

Glossary
065307 Tandem Computers Incorporated Glossary–3
CLIP. Communications line interface processor. The CLIP is the part of the line
interface unit (LIU) in the 3650/6100 family controllers. Code can be downloaded to
the CLIP to provide a link-level protocol.
CMI. Communications Management Interface. A subsystem used for issuing
configuration and information requests between the user and some communications
subsystems. CMI is not supported for D-series X25AM. Also, it does not support all
features of X25AM for C-series systems.
combined station. A station configuration, connecting a point-to-point link, where each
station shares link management responsibility. Either station can transmit to the other
without first seeking permission to do so. This is the type of configuration prescribed
by LAPB for X.25 connections.
common carrier. Company that furnishes communications services to the public and is
regulated by appropriate state or federal agencies.
Communications Management Interface. See CMI.
communications subsystem. Collection of hardware and software that provides a specific
communications function (for example, communications between a Tandem system
and an X.25 network).
CONFTEXT. An input file for the SYSGEN (system-image generation) program, which
specifies the hardware and system-software configuration for a Tandem system.
conversation mode. Data transmission mode for a terminal. Transmitted data messages
consist of single characters instead of groups of characters.
COUP. Configuration Utility Program. User interface for the Dynamic System
Configuration (DSC) program. COUP is used for online configuration.
CPADPARMS. Conversational mode options, which can be set by the user, for
configuring a Packet Assembler/Disassembler (PAD).
C-series system. A system running a C-series version of the Guardian 90 operating
system. A C-series system allows a maximum of 256 concurrent processes in a CPU.
CSM. Communications Subsystem Manager. Process coordinating certain functions
for 3650/6100 Communications Family. The CSM is responsible for downloading
microcode to the controllers.
CUD. Call user data. An optional field contained in call setup packets. Can be used to
transmit higher-level protocol information. Do not confuse the CUD with the user
data field, which appears in data packets and contains the user data.
CUG. Closed user group. Optional network facility restricting calls to members
assigned to a group.
CUP. Communications Utility Program. This program was replaced by CMI and then
by SCF. CUP is an older program with less functions than its replacements. It is not
supported on D-series systems.
D bit. Delivery confirmation bit. A part of the packet header, it can be used to request
end-to-end acknowledgement of data packets.