X25AM Configuration and Management Manual

Glossary
X25AM Configuration and Management Manual—523424-004
Glossary-5
IOP
IOP. I/O process. System process that controls input and output, usually to and from a
device.
ISO. See International Organization for Standardization (ISO).
ITI protocol. Interactive terminal Interface protocol. For X25AM, it is used by the X25AM
process when an application exchanges data with a remote terminal connected to an
X.25 packet-switching network with a PAD.
ITU. International Telecommunication Union (ITU), and its Telecommunication
Standardization Sector (ITU-T), which is responsible for studying technical, operating,
and tariff questions and issuing Recommendations on them with a view to
standardizing telecommunications on a worldwide basis.
LAP. See Link Access Procedure (LAP) and Link Access Procedure in a Balanced System
(LAP and LAPB).
LAPB. See Link Access Procedure (LAP) and Link Access Procedure in a Balanced System
(LAP and LAPB).
leased line. Telephone line reserved for exclusive (private) use of the leasing customer.
link. Call or transmission path (including all equipment) between a sender and receiver.
Link Access Procedure (LAP) and Link Access Procedure in a Balanced System (LAP
and LAPB). Procedures used in a packet-switching network for data interchange
across the access link between a network and the computers, terminals, or other
devices. Responsible for activities involving framing, synchronization control, and error-
detection.
link layer. See frame layer.
logical channel. Means of two-way communications between two network entities.
logical channel number. Number assigned to a logical channel to uniquely identify it.
logical device. Device that can be accessed and addressed. It may not be equivalent to a
physical device.
management information base (MIB). An Enscribe indexed file used to hold the wide area
network (WAN) subsystem configuration records. The MIB is built, maintained, and
accessed by the WAN manager process.
message. Complete communications sent as a unit, able to be queued and assigned
priorities.
message control word. First 2 bytes (1 word) of a message in the application buffer; it
contains message control information. Used in a user-coded program utilizing the PTP
application protocol.