IBM 8237 Installation And User Manual page 159

more diskette drives, internal fixed-disk storage, and an
optional printer. PCs are designed primarily to give
independent computing power to a single user and are
inexpensively priced for purchase by individuals or
small businesses.
physical connection. The ability of two connectors to
mate and make electrical contact. In a network,
devices that are physically connected can
communicate only if they share the same protocol. See
also logical connection.
platform. (1) The operating system environment in
which a program runs. (2) In computer technology, the
principles on which an operating system is based.
plug. (1) A connector designed to insert into a
receptacle or socket. (2) To insert a connector into a
receptacle or socket.
port. (1) An access point for data entry or exit. (2) A
connector on a device to which cables for other devices
such as display stations and printers are attached.
POST. Power-on self-test.
power-on self-test (POST). A series of diagnostic
tests that are run automatically each time the
computer's power is turned on.
procedure. A set of instructions that gives a service
representative a step-by-step procedure for tracing a
symptom to the cause of failure.
protocol. (1) A set of semantic and syntactic rules that
determines the behavior of functional units in achieving
communication. (I) (2) A specification for the format and
relative timing of information exchanged between
communicating parties.
R
rack. Synonym for equipment rack.
random access memory (RAM). A computer's or
adapter's volatile storage area into which data may be
entered and retrieved in a nonsequential manner.
receive. To obtain and store information transmitted
from a device.
repeater. In a network, a device that amplifies or
regenerates data signals in order to extend the
distance between attaching devices.
repeater hop. Counted when a frame passes through
a repeater or its equivalent.
Reverse Address Resolution Protocol (RARP). A
protocol that maintains a database of mappings
between physical hardware addresses and IP
addresses.
RFC. Request for comments.
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8237 Hub Installation and Planning Guide
router. An attaching device that connects two LAN
segments, which use similar or different architectures,
at the reference model network layer. Contrast with
bridge and gateway .
Routing Information Protocol (RIP). In the Internet
suite of protocols, an interior gateway protocol used to
exchange intradomain routing information and to
determine optimum routes between internet hosts. RIP
determines optimum routes on the basis of route
metrics, not link transmission speed.
S
SAP. (1) Service access point. (2) Service Advertising
Protocol.
ScTP. Screened twisted pair.
segment. See cable segment, LAN segment .
serial. (1) Pertaining to a process in which all events
occur one after the other; for example, serial
transmission of the bits of a character according to V24
CCITT protocol. (T) (2) Pertaining to the sequential or
consecutive occurrence of two or more related activities
in a single device or channel. (A) (3) Pertaining to the
sequential processing of the individual parts of a whole,
such as the bits of a character or the characters of a
word, using the same facilities for successive parts. (A)
Serial Line Internet Protocol (SLIP). A simple form of
encapsulation for IP frames that enables them to travel
over serial lines.
serial port. On personal computers, a port used to
attach devices such as display devices, letter-quality
printers, modems, plotters, and pointing devices such
as light pens and mice; it transmits data 1 bit at a time.
Contrast with parallel port.
server. (1) A device, program, or code module on a
network dedicated to providing a specific service to a
network. (2) On a LAN, a data station that provides
facilities to other data stations. Examples are a file
server, print server, and mail server.
Service Advertising Protocol (SAP). In Internetwork
Packet Exchange (IPX), a protocol that provides the
following:
•
A mechanism that allows IPX servers on an
internet to advertise their services by name and
type. Servers using this protocol have their name,
service type, and internet address recorded in all
file servers running NetWare.
•
A mechanism that allows a workstation to
broadcast a query to discover the identities of all
servers of all types, all servers of a specific type,
or the nearest server of a specific type.