IBM Cloud Object Storage System Slicestor 2212..., Руководство по обслуживанию и ремонту

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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) The representation of a
physical connection to the link hardware. A port is
sometimes referred to as an adapter; however, there
can be more than one port on an adapter. There may
be one or more ports controlled by a single DLC
process. (4) In the Internet suite of protocols, a 16-bit
number used to communicate between TCP or the User
Datagram Protocol (UDP) and a higher-level protocol or
application. Some protocols, such as File Transfer
Protocol (FTP) and Simple Mail Transfer Protocol
(SMTP), use the same well-known port number in all
TCP/IP implementations. (5) An abstraction used by
transport protocols to distinguish among multiple
destinations within a host machine.
PPP. Point-to-Point Protocol.
private branch exchange (PBX). A private telephone
exchange for transmission of calls to and from the
public telephone network.
problem determination. The process of determining
the source of a problem; for example, a program
component, machine failure, telecommunication
facilities, user or contractor-installed programs or
equipment, environmental failure such as a power loss,
or user error.
PRS. Primary reference source.
PSN. Public switched network.
PSTN. Public switched telephone network.
PTM. Packet transfer mode.
PVC. Permanent virtual circuit.
Q
QoS. Quality of service.
R
rack. A metallic structure, with a standard 19-inch
width, that houses Nways Switch hardware elements:
logic subrack with modules, fan boxes, and power
subrack with power units.
real-time processing. The manipulation of data that
are required, or generated, by some process while the
process is in operation. Usually the results are used to
influence the process, and perhaps related processes,
while it is occurring.
RETAIN. Remote Technical Assistance Information
Network.
ring. See ring network.
ring network. (1) A network in which every node has
exactly two branches connected to it and in which there
are exactly two paths between any two nodes. (T)
(2) A network configuration in which devices are
connected by unidirectional transmission links to form a
closed path.
route. (1) An ordered sequence of nodes and
transmission groups (TGs) that represent a path from
an origin node to a destination node traversed by the
traffic exchanged between them. (2) The path that
network traffic uses to get from source to destination.
router. (1) A computer that determines the path of
network traffic flow. The path selection is made from
several paths based on information obtained from
specific protocols, algorithms that attempt to identify the
shortest or best path, and other criteria such as metrics
or protocol-specific destination addresses. (2) 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. (3) In OSI terminology, a function that
determines a path by which an entity can be reached.
routing. (1) The assignment of the path by which a
message is to reach its destination. (2) In SNA, the
forwarding of a message unit along a particular path
through a network, as determined by parameters carried
in the message unit, such as the destination network
address in a transmission header.
RSC. Remote Support Center.
RSF. Remote Support Facility.
RT. Real time.
S
s. Second.
SDH. Synchronous digital hierarchy.
SDLC. Synchronous Data Link Control.
SDT. Structured data transfer.
SF. Super Frame.
Serial Line Internet Protocol (SLIP). A TCP/IP
protocol used on a point-to-point connection between
two IP hosts over a serial line (for example, an
RS/EIA-232 connection into a modem over a telephone
line).
Glossary
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