HP 316095-B21 - StorageWorks Edge Switch 2/24 User Manual page 134

Glossary
blocked connection
In S/390 mode, in a Director or Switch, the attribute that, when set, removes the
communication capability of a specific port. A blocked address is disabled so that no other
address can be connected to it. A blocked attribute supersedes a dedicated or prohibited
attribute on the same address. Contrast with unblocked connection. See also connectivity
attribute; dynamic connection; dynamic connectivity.
blocked port
In a Director or Switch, the attribute that when set, removes the communication capability of a
specific port. A blocked port continuously transmits the offline sequence.
buffer
Storage area for data in transit. Buffers compensate for differences in processing speeds
between devices. See also buffer-to-buffer credit.
buffer-to-buffer credit
BB_Credit. (1) The maximum number of receive buffers allocated to a transmitting node port
(N_Port) or fabric port (F_Port). Credit represents the maximum number of outstanding
frames that can be transmitted by that N_Port or F_Port without causing a buffer overrun
condition at the receiver. (2) The maximum number of frames a port can transmit without
receiving a receive ready signal from the receiving device. BB_Credit can be adjustable to
provide different levels of compensation.
bus
The path that carries data between the computer (microprocessor) and peripheral devices. An
IDE interface cable and a small computer system interface (SCSI) cable are both examples.
bypassed port
If a port is bypassed, all serial channel signals route past the port. A device attached to the port
cannot communicate with other devices in the loop.
cascade
Linking two or more Fibre Channel switches to form a larger switch or fabric. The switched
link through fiber cables attached between one or more expansion ports (E_Ports). See also
expansion port
channel
(1) A system element that controls one channel path, and whose mode of operation depends on
the type of hardware attached. Each channel controls an I/O interface between the channel
control element and the attached control units (D). (2) Point-to-point link that transports data
from one point to the other. (3) A connection or socket on the motherboard to controller card.
A motherboard may have only one or two channels (primary and secondary). If a motherboard
has only one channel, it may be necessary to add a controller card to create a secondary
channel.
Glossary–4 embedded web server user guide