Telserv Manual

Glossary
Telserv Manual—427174-009
Glossary-2
ECHO
ECHO. The name of a program used in the Internet to test the reachability of destinations by
sending them an ICMP echo request and waiting for a reply.
emulator. A software program that enables a device to simulate the functions of another
software or hardware device. For example, the PC6530 terminal emulator program
(PCT) enables your workstation to simulate the functions of a 65-Series terminal.
error. A condition that causes a command or other operation to fail.
event management. The reporting and logging of events, the distribution and retrieval of
information concerning those events, and the actions taken by operations personnel or
software in response to the events.
Event Management Service (EMS). A part of DSM used to provide event collection, event
logging, and event distribution facilities. It provides for different event descriptions for
interactive and programmatic interfaces, lets an operator or application select specific
event-message data, and allows for the flexible distribution of event messages within a
system or network. EMS has an SPI-based programmatic interface for both reporting
and retrieving events.
event message. A special kind of SPI message that describes an event occurring in the
system or network.
event. In DSM terms, a significant change in some condition in the system or network.
Events can be operational errors, notifications of limits exceeded, requests for action
needed, and so on.
File Transfer Protocol (FTP). The Internet standard, high-level protocol for transferring files
from one machine to another. Usually implemented as application level programs, FTP
uses the TELNET and TCP protocols. The server side requires a client to supply a
login identifier and password before it will honor requests.
full-duplex mode. The communication mode in which data can be transferred in both
directions simultaneously. In the Session Layer, no data token is needed.
half-duplex mode. The communications mode in which data can be transferred in both
directions, but only in one direction at a time, and in which the direction of data flow
alternates. In the Session Layer, the data token indicates which side can send data.
hop count. A measure of distance between two points in the Internet. A hop count of n
means that n gateways separate the source destination.
Internet. Physically, a collection of packet switching networks interconnected by gateways,
along with protocols that allow them to function logically as a single, large, virtual
network. When written in uppercase, INTERNET refers specifically to the DARPA
Internet and the TCP/IP protocols it uses.