IBM Nways 2216, Руководство по обслуживанию и ремонту

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autonomous system (AS). A group of networks and
routers that use the same interior gateway protocol and
for which one administrative authority has responsibility.
B
Bc. Committed burst size.
Be. Excess burst size.
bps. Bits per second.
bridge. A functional unit that interconnects multiple
LANs (locally or remotely) that use the same logical link
control protocol but that can use different medium
access control protocols. A bridge forwards a frame to
another bridge based on the medium access control
(MAC) address.
bridging. In LANs, the forwarding of a frame from one
LAN segment to another. The destination is specified
by the medium access control (MAC) sublayer address
encoded in the destination address field of the frame
header.
broadband. A large frequency band allowing different
kinds of transmissions, such as coded voice, video, and
data, at the same time.
BSC. Binary synchronous communication.
C
CAS. Channel associated signaling.
CCITT. International Telegraph and Telephone
Consultative Committee. This was an organization of
the International Telecommunication Union (ITU). On 1
March 1993 the ITU was reorganized, and
responsibilities for standardization were placed in a
subordinate organization named the Telecommunication
Standardization Sector of the International
Telecommunication Union (ITU-TS). “CCITT” continues
to be used for recommendations that were approved
before the reorganization.
CCS. (1) common channel signaling (2) change control
server.
CDB. Configuration database.
CES. Circuit emulation service.
channelization. The process of breaking the
bandwidth on a communication line into a number of
channels, possibly of different size. Also called
time
division multiplexing (TDM).
CIR. Committed information rate.
circuit. (1) One or more conductors through which an
electric current can flow. See
physical circuit and virtual
circuit. (2) A logic device.
circuit switching. (1) A process that, on demand,
connects two or more data terminal equipment (DTEs)
and permits the exclusive use of a data circuit between
them until the connection is released. (I) (A)
(2) Synonymous with
line switching.
CMIP. Common Management Information Protocol.
CMIS. Common Management Information Services.
CMOT. CMIP over TCP/IP.
CNM. Communication network management.
configuration. (1) The manner in which the hardware
and software of an information processing system are
organized and interconnected. (T) (2) The devices and
programs that make up a system, subsystem, or
network.
connection. In data communication, an association
established between functional units for conveying
information. (I) (A)
CP. Control point.
CRC. Cyclic redundancy check.
CU logical address. The control unit (CU) address
defined in the host for the 2216. This value is defined
in the host Input/Output Configuration Program (IOCP)
by the CUADD statement on the CNTLUNIT macro
instruction. The control unit address must be unique for
each logical partition defined on the same host.
D
DAS. Dual attaching system (for FDDI).
data circuit. (1) A pair of associated transmit and
receive channels that provide a means of two-way data
communication. (I) (2) See also
physical circuit and
virtual circuit.
Notes:
1. Between data switching exchanges, the data circuit
may include data circuit-terminating equipment
(DCE), depending on the type of interface used at
the data switching exchange.
2. Between a data station and a data switching
exchange or data concentrator, the data circuit
includes the data circuit-terminating equipment at
the data station end, and may include equipment
similar to a DCE at the data switching exchange or
data concentrator location.
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2216 Maintenance Manual