HP Mainframe Connectivity Design Guide

BB_credits Buffer-to-buffer credits.
C
C-series FICON directors manufactured for HP by Cisco Systems, Inc.
cascaded switch The destination director attached to the CU.
CCW Channel command word. A device command that can be linked with other CCWs to form a
channel program. This is the mainframe equivalent of a Fibre Channel SCSI command.
CEE Converged enhanced Ethernet.
CF Coupling facility. A hardware device that provides a high-speed interface and connections for
intersystem and intrasystem communications.
channel A hardware device that connects the mainframe to the fabric.
channel path The physical channel interface (port) on the mainframe.
channel program A series of CCWs that control an I/O operation or series of I/O operations for a CU.
CHPID Channel path identifier. A number assigned to the channel path, used as an address for the
channel interface. Also used to refer to a mainframe channel.
CICS Customer Information Control System. A transaction manager designed for rapid, high-volume
online processing.
CKD Check key data. A standard IBM file structure for disk volumes.
CMF CICS Monitoring Facility. A facility that collects data about all transactions in the CICS region
during online processing, and writes the data as SMF records.
control unit See CU.
controller pair Two connected controller modules that control a disk array.
CP See CPC.
CPC Central processor complex. A board that contains multiple processor chipsets. This is the mainframe
equivalent of CPU.
CSR Customer Self Repair. A hardware designation indicating that parts are designed to be replaced
by customers.
CSS Channel subsystem.
CTC Channel-to-channel, used for application-to-application communication.
CU Control unit. Hardware and software that controls access to I/O devices and provides an interface
to the mainframe channel. This is the mainframe equivalent of a Fibre Channel target.
CUADD Control unit address. The mainframe designation for the LCU or CU image.
CUNUMBER Control unit number. A user-specified number that uniquely identifies a CU in the mainframe
configuration.
CUP Control unit port. An optional feature used to manage and monitor FICON directors.
CWDM Coarse wavelength division multiplexing. The technique of placing more than one optical signal
on a single optical cable simultaneously.
See also WDM.
D
dark fiber Dedicated fiber link.
DAS Direct-attached storage.
DASD Direct access storage device. A disk array device or volume.
DCC Device Connection Control. A data access policy that determines to which switch ports a Fibre
Channel device can connect.
DCFM Data Center Fabric Manager software.
device The disk volume configured for each CU in a storage system. Also known as the logical device
(LDEV), disk volume, or volume. This is the mainframe equivalent of a LUN.
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