IBM Nways 2216, Руководство по обслуживанию и ремонту

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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.
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).
In an NBBS network, the SLIP is used over a
connection between an Nways Switch administration
station (NAS) and an IBM Network Support Center
(NSC).
Simple Network Management Protocol (SNMP). In
the Internet suite of protocols, a network management
protocol that is used to monitor routers and attached
networks. SNMP is an application layer protocol.
Information on devices managed is defined and stored
in the application's Management Information Base
(MIB).
SLA. Serial link architecture.
SLIP. Serial Line Internet Protocol.
SNA. Systems Network Architecture.
SNMP. Simple Network Management Protocol.
socket. The abstraction provided by the University of
California's Berkeley Software Distribution (commonly
called Berkeley UNIX or BSD UNIX) that serves as an
endpoint for communication between processes or
applications.
SONET. Synchronous optical network.
source route bridging. In LANs, a bridging method
that uses the routing information field in the IEEE 802.5
medium access control (MAC) header of a frame to
determine which rings or token-ring segments the frame
must transit. The routing information field is inserted
into the MAC header by the source node. The
information in the routing information field is derived
from explorer packets generated by the source host.
spoofing. For data links, a technique in which a
protocol initiated from an end station is acknowledged
and processed by an intermediate node on behalf of the
final destination. In IBM 6611 data link switching, for
example, SNA frames are encapsulated into TCP/IP
packets for transport across a non-SNA wide area
network, unpacked by another IBM 6611, and passed to
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2216 Maintenance Manual