IBM 8285 Nways, Installation And User Manual

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directly or through one or more frame-relay frame
handlers. A PVC consists of one or more PVC
segments.
PING. Packet Internet Groper.
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.
Synonymous with
socket. (3) A PHY entity and a PMD
entity in a node, together creating a PHY/PMD pair, that
may connect to the fiber media and provide one end of a
physical connection with another node.
POST. Power-on self-test.
power budget. Synonym for fiber budget.
power-on self-test (POST). A series of diagnostic tests
that are run automatically by a device when the power is
switched on.
protocol. (1) A set of semantic and syntactic rules that
determines the behavior of functional units in achieving
communication. (I) (2) In SNA, the meanings of and the
sequencing rules for requests and responses used for
managing the network, transferring data, and
synchronizing the states of network components. (3) A
specification for the format and relative timing of
information exchanged between communicating parties.
PS/2. Personal System/2.
PVC. Permanent virtual connection.
Q
QOS. Quality of service
quality of service (QOS). A set of communication
characteristics required by an application. Each QOS
defines a specific transmission priority, level of route
reliability, and security level. Each QOS also defines
whether the sessions are interactive.
R
rack. Synonym for equipment rack.
RAM. Random access memory.
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.
receiver (optical). An optoelectronic circuit that
converts an optical signal to an electrical logic signal.
remote. (1) Pertaining to a system, program, or device
that is accessed through a telecommunication line.
(2) Contrast with
local.
Request for Comments (RFC). In Internet
communications, the document series that describes a
part of the Internet suite of protocols and related
experiments. All Internet standards are documented as
RFCs.
RFC. Request for Comments.
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. (1) The assignment of the path by which a
message will reach its destination. (2) In SNA, the
forwarding of a message unit along a particular path
through a network, as determined by the parameters
carried in the message unit, such as the destination
network address in a transmission header.
RS-232. In data communications, a specification of the
Electronic Industries Association (EIA) that defines the
interface between data terminal equipment (DTE) and
data circuit-terminating equipment (DCE), using serial
binary data interchange.
RX. Receive.
S
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.
session. (1) In network architecture, for the purpose of
data communication between functional units, all the
activities which take place during the establishment,
maintenance, and release of the connection. (T)
(2) The period of time during which a user of a terminal
can communicate with an interactive system, usually,
elapsed time between logon and logoff.
SFTP. Screened and foiled twisted pair.
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IBM 8285 Nways ATM Workgroup Switch: Installation and User’s Guide