OSI/MHS Orientation Guide

Glossary
OSI/MHS Orientation Guide—424829-001
Glossary-14
MTS (message transfer system). The part of a message handling system that contains the
MTAs and that permits communication between user agents.
MTS identifier. A unique identifier that distinguishes a communication from all other
communications ever conveyed by the MTS within the MHS.
multithreaded process. A process that handles multiple requests simultaneously.
multivalued attribute. An attribute that can have more than one value.
network address. See NSAP and NSAP address.
Network Layer. Layer 3 in the OSI Reference Model. This layer routes data by establishing,
maintaining, and terminating communications between nodes. It sets up the most
economical path, both physical and logical, between communicating nodes; routes
messages through intervening nodes to their destinations; and controls the flow of
messages between nodes.
network service access point. See NSAP or NSAP address.
node. In general, a system or device that follows the protocols of a specific network and that
other systems or devices in that network can address.
In Expand (the Compaq proprietary network), a computer system that is part of a
Compaq Expand network of computer systems. A node address is designated by a
symbol before the name (for example, \NY in file names or @NY in Transfer
correspondent names).
nonadjacent MTA. An MTA in the X.400 network that has no direct path to your OSI/MHS
subsystem. See also adjacent MTA or remote MTA.
noncritical event. A DSM event that is not crucial to system or network operations. Each
subsystem determines which of its events are noncritical by setting the value of the
emphasis token to FALSE. See also critical event.
nonconfigured object. An object whose characteristics have not been specified to OSI/MHS
through SCF or through a management application that issues programmatic commands.
See also configured object.
nondelivery report. A communication directed by an MTA toward the originator of a
message, indicating why the message could not be delivered to the UA of its intended
recipient, and including trace and diagnostic information.
nonreceipt notification. An indication to the sender of a communication that the
communication was not received by the intended recipients.
nonsensitive command. A DSM command that can be issued by any user or program having
access to the target subsystem—that is, a command on which the subsystem imposes no
further security restrictions. For Compaq data communications subsystems, the
nonsensitive commands are usually information commands (commands that cannot
change the state or configuration of objects). See also sensitive command.
NonStop Kernel. The operating system, which consists of the core and system services. The
operating system does not include any application program interfaces.