SNMP Configuration and Management Manual

Glossary
SNMP Configuration and Management Manual—424777-006
Glossary-7
internet layer
test whether a destination is reachable and responding. This protocol is used by the
network layer to communicate the reachability of particular network nodes and routing
control information. Strictly speaking, ICMP is part of the IP protocol because it shares
the same Ethernet type field.
internet layer. The layer in the Internet suite of protocols responsible for providing
transparency over both the topology of the Internet and the transmission media used in
each physical network.
Internet Protocol. The network protocol in the Internet suite of protocols. It defines the
internet datagram as the basic unit of information exchanged on an internet network,
and it provides the basis for a connectionless, best-effort packet delivery service.
Internet suite of protocols. A collection of communications protocols originally developed
under DARPA sponsorship; currently, the de facto solution of open networking. The
Internet suite of protocols can be viewed as having four layers: interface, internet,
transport, and application.
IP. See Internet Protocol.
IP group. The group in MIB-II supported by the TCP/IP Subagent that provides information
about the IP layer of a TCP/IP subsystem being managed.
LAN. See local area network.
leaf. In an object tree, a node without subordinates.
lexicographic ordering. The ordering exhibited by object identifiers, which are expressed
as integers. Lexicographic ordering extends to object-instance identifiers, since an
object-instance identifier is also a sequence of integers. This ordering allows managers
to search for and access objects without specifying them by name. By using
lexicographic ordering, a manager can traverse the structure of a MIB, At any point in
the tree, the manager can supply an object or object-instance identifier and ask for the
object instance that occurs next in the ordering.
LIF. See logical interface (LIF).
llocal area network. Any one of a number of technologies providing high-speed, low-
latency data transfer among electronic entities at a single site.
LOCPROC. The NonStop NET/MASTER MS process that manages EMS event messages
logged to a file.
log file. A file to which an EMS collector writes events it receives from subsystems and
applications.
logical interface (LIF). In a G-series ServerNet environment, the process that allows an
application or another process to communicate with data communications hardware.