Glossary
User Guide
445
RISC
Reduced Instruction Set Computer. This describes a computer processor architecture that
uses a reduced set of instructions (and achieves performance by executing those instructions
very fast.) Most UNIX servers (Sun Sparc, HP, IBM RS6000, Compaq Alpha) were designed
with a processor using a RISC architecture. The Intel
®
x86 architecture.
RS-232
A set of standards for serial communication between electronic equipment defined by the
Electronic Industries Association in 1969. Today, RS-232 is still widely used for low-speed data
communication.
Secure Shell (SSH)
SSH has the same functionality as Telnet (see definition below), but adds security by encrypt-
ing data before sending it through the network.
Server Farm
A collection of servers running in the same location (see Cluster).
SNMP
Short for Simple Network Management Protocol, a set of protocols for managing complex
networks. The first versions of SNMP were developed in the early 80s. SNMP works by send-
ing messages, called protocol data units (PDUs), to different parts of a network. SNMP-com-
pliant devices, called agents, store data about themselves in Management Information Bases
(MIBs) and return this data to the SNMP requesters. (Source: Webopedia)
Telnet
Telnet is the standard set of protocols for terminal emulation between computers over a TCP/
IP connection. It is a terminal emulation program for TCP/IP networks such as the Internet.
The Telnet program runs on your computer and connects your PC to a server on the network.
You can then enter commands through the Telnet program and they will be executed as if
you were entering them directly on the server console. This enables you to control the server
and communicate with other servers on the network. To start a Telnet session, you must log
in to a server by entering a valid username and password. Telnet is a common way to
remotely control Web servers. (from webopedia.com)
