IBM xSeries 300, Service Manual

Page: 148 / 160

bridge. A functional unit that interconnects two local
area networks. A bridge works at the data link level
(layer 2) of the OSI reference model.
broadband network. A network that uses a large
frequency band to transport different kinds of traffic
(such as coded voice, video, and data) at the same
time.
BS. Bearer services.
BSC. Binary synchronous communication.
BSP. Bearer service profile.
BT. Burst tolerance.
bursty. Refers to transmission at variable bit rate
where the time between data transmissions is not
always the same.
CAC. Connection admission control.
CAS. Channel associated signaling.
CBR. Constant bit rate.
CCS. (1) Common channel signaling (2) Change
control server (also called CC server).
CDB. Configuration database.
CDV. Cell delay variation.
CDVT. Cell delay variation tolerance.
cell loss priority (CLP). A priority bit in the ATM cell
header. When set, it indicates that the cell can be
discarded during traffic congestion.
centralized configuration database. A database
prepared with the Nways Switch Configuration Tool
Version 2 (NCT2) on a configuration station. It stores
the parameters of a 2220 network.
CES. Circuit emulation services.
change control server (CCS or CC server). A station
that runs the IBM NetView Distribution Manager for AIX
to store the Nways Switch Control Program and to
manage code changes.
CIR. Committed information rate.
circuit emulation services (CES). An access service
that emulates a leased line. It transports information
with a constant bit rate at the source and destination.
The traffic can be PCM voice, video, fax, multimedia, or
real-time synchronous data (such as BSC).
CLIP. Calling line identification presentation.
CLIR. Calling line identification restriction.
CLK. Clock (module).
CLKRD. Clock redrive (module).
clock module (CLK). A module of the 2220 Model
300 or 500 that transmits clock signals to the line
interface couplers (LICs). It is optional and can have a
backup.
clock redrive (CLKRD). A module of the 2220 Model
501 that drives the signals from the Model 500 clock
module to the adapters of the Model 501. The clock
redrive is optional and can have a backup.
clock references. In an Nways Switch, the software
function that controls the transmission of clock signals
to the LICs where they are used for bit synchronization.
CLP. Cell loss priority.
CMIP. Common management information protocol.
CMIS. Common management information services.
CMOT. CMIP over TCP/IP.
CNM. Communication network management.
code file. A named set of records stored as a unit in a
change control server. An Nways Switch code file can
include data or internal code.
COLP. Connected line identification presentation.
COLR. Connected line identification restriction.
configuration station. See Nways Switch
configuration station.
control point (CP). In an Nways Switch, a logical
resource that provides network control functions. It can
have a backup.
CP. Control point.
CPA. Control point adapter (module).
CPE. Customer premises equipment.
CP spanning tree. In a 2220 network, a distribution
tree that connects the Nways Switch control points
through trunk lines.
The CP spanning tree supplies a very fast and efficient
way to multicast control messages such as network
topology data.
CRC. Cyclic redundancy check.
CSU. Channel access unit.
CTD. Cell transfer delay.
data circuit-terminating equipment (DCE). An
equipment installed on a user premises that provides all
the functions required to establish, maintain, and
terminate a connection, and to do the signal conversion
E-2
2220 Setup and Service Guide