TCP/IP Configuration and Management Manual

Glossary
TCP/IP Configuration and Management Manual—427132-004
Glossary-5
Ethernet
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 all contain 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 4 ServerNet adapter (E4SA). A ServerNet adapter for Ethernet local area
networks (LANs) that contains four Ethernet ports.
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 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. See also DSM
or event message.
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 message. A special kind of SPI message that describes an event occurring in the
system or network. Compare
command message.
Expand. The Expand subsystem enables you to link together as many as 255
geographically dispersed NonStop systems to create a network with the same
reliability, capacity to preserve data integrity, and potential expansion as a single
NonStop system.
extensible structure. In DSM programmatic interfaces, a structure declared for the value of
an extensible structured token.
See also extensible structured token. Compare fixed
structure.
extensible structured token. In DSM programmatic interfaces, a token consisting of a
token code and a value that is an extensible structure. Extensible structures can be
extended by adding new fields at the end in later RVUs. Such structures are typically
used to indicate the attributes of an object being operated on and to return status and
statistics information in responses; they can also be used for other purposes. The
token is referenced by a token map that describes the structure to SPI so that SPI can
provide compatibility between different versions of the structure.