IPX/SPX Programming Manual

Glossary
HP NonStop IPX/SPX Programming Manual—528022-001
Glossary-4
EGP
EGP. (Exterior Gateway Protocol) The protocol used by a gateway in one autonomous
system to advise the Internet addresses of networks in that autonomous system to a
gateway in another autonomous system. Every autonomous system must use EGP to
advertise network reachability to the core gateway system.
empty. response record. In DSM programmatic interfaces, a response record containing
only a return token with a value that means “no more response records.”
EMS. See Event Management Service (EMS).
error. In DSM interfaces, a condition that causes a command or other operation to fail.
Contrast warning.
Ethernet. A popular local area network technology invented at the Xerox Corporation Palo
Alto Research Center. An Ethernet itself is a passive coaxial cable; the
interconnections contain all active components. Ethernet is a best-effort delivery
system that uses CSMA/CD technology. Xerox Corporation, Digital Equipment
Corporation, and Intel Corporation developed and published the standard for 10 Mbps
Ethernet.
Ethernet meltdown. An event that causes saturation or near saturation on an Ethernet.
It usually results from incorrect or misrouted packets and typically lasts only a short
time. As an example, consider an IP datagram directed to a nonexistent host and
delivered by way of hardware broadcast to all machines on the network. Gateways
receiving the broadcast will send out ARP packets in an attempt to find the host and
deliver the datagram.
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.
event log. A file or set of files maintained by EMS to store event messages generated by
subsystems.
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. Compare control and inquiry.
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. See also Distributed Systems Management and event.
filter. In EMS, a file containing a list of criteria against which incoming event messages can
be compared. The messages are allowed to pass (all criteria met) or not pass (one or
more criteria failed).