NonStop NS-Series Planning Guide (H06.03+)

Glossary
HP Integrity NonStop NS-Series Planning Guide—529567-004
Glossary-8
release version update (RVU)
range. At present, the terms radio frequency interference and electromagnetic
interference (EMI) are usually used interchangeably.
release version update (RVU). A collection of compatible revisions of HP NonStop
operating system software products, identified by an RVU ID, and shipped and
supported as a unit. An RVU consists of the object modules, supporting files, and
documentation for the product revisions. An RVU also includes a set of documentation
for the overall RVU.
RFI. See radio frequency interference (RFI).
rms. See root mean square (rms).
root mean square (rms). A measurement method used to determine the direct current
(DC) equivalent value for alternating voltage and current waveforms. The rms method
refers to the process of sampling a waveform, squaring the samples, averaging the
samples (mean value) over the period from one cycle, and then calculating the square
root of the samples. In general, rms-sensing devices are more accurate than averaging
meters. Measurements from averaging meters can be as low as 30 percent of the
actual current for loads with high crest factors.
RS-232. An industry standard for serial data transmission. It describes pin assignments,
signal functions, and electrical characteristics. The current standard specifies a 25-pin
connector.
RS-449. An industry standard for serial data transmission. It specifies pin assignments,
signal functions, electrical characteristics, and a 37-pin connector with an optional
9-pin connector for a secondary channel.
RVU. See release version update (RVU).
S-series servers. See HP NonStop™ S-series servers.
server. (1) An implementation of a system used as a stand-alone system or as a node in an
Expand network. (2) A combination of hardware and software designed to provide
services in response to requests received from clients across a network. For example,
HP NonStop™ servers provide transaction processing, database access, and other
services. (3) A process or program that provides services to a client or a requester.
Servers are designed to receive request messages from clients or requesters; perform
the desired operations, such as database inquiries or updates, security verifications,
numerical calculations, or data routing to other computer systems; and return reply
messages to the clients or requesters. A server process is a running instance of a
server program.
ServerNet. A communications protocol developed by HP that is used in HP NonStop™
S-series servers. See also ServerNet I and ServerNet II.
ServerNet I. The first-generation ServerNet network. ServerNet I architecture is used in HP
NonStop™ S-series servers and other products. It features 50 megabytes/second