IBM TotalStorage 3534-F08, Installation Manual

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basic input/output system (BIOS). Code that controls
basic hardware operations, such as interactions with
diskette drives, hard disk drives, and the keyboard.
BB. Buffer-to-buffer.
BB_Credit. See buffer-to-buffer credit.
beginning running disparity. The disparity at the
transmitter or receiver when the special character
associated with an ordered set is encoded or decoded.
See also disparity.
BER. See bit error rate.
BIOS. See basic input/output system.
BISR. Built-in self-repair.
bit error rate. The rate at which bits are expected to
be received in error. Expressed as the ratio of error bits
to total bits transmitted. See also error.
block. As applies to fibre channel, upper-level
application data that is transferred in a single sequence.
bloom. Application-specific integrated circuit (ASIC)
technology that the 3534 Model F08 is based on.
broadcast. The transmission of data from a single
source to all devices in the fabric, regardless of zoning.
See also multicast and unicast.
BTU. British thermal unit.
buffer-to-buffer credit. The number of frames that
can be transmitted to a directly-connected recipient or
within an arbitrated loop. Determined by the number of
receive buffers available. See also buffer-to-buffer flow
control, end-to-end credit.
buffer-to-buffer flow control. Management of the
frame transmission rate in either a point-to-point
topology or in an arbitrated loop. See also
buffer-to-buffer credit.
CAM. Content addressable memories.
cascade. Two or more interconnected fibre-channel
switches. Switches can be cascaded up to 239
switches, with a recommended maximum of seven
inter-switch links (no path longer than eight switches).
See also fabric, inter-switch link.
cascading switches. Switches that are interconnected
to build large fabrics.
central processing unit (CPU). A part of a computer
that includes the circuits that control the interpretation
and execution of instructions. A CPU in the circuitry and
storage that executes instructions. Traditionally, the
complete processing unit was often regarded as the
CPU, whereas today the CPU is often a microchip. In
either case, the centrality of a processor or processing
unit depends on the configuration of the system or
network in which it is used.
chassis. The metal frame in which the switch and
switch components are mounted.
circuit. An established communication path between
two ports. Consists of two virtual circuits capable of
transmitting in opposite directions. See also link.
class F. Connectionless service for inter-switch control
traffic. Provides notification of delivery or nondelivery
between two E_ports.
class 1. Service that provides a dedicated connection
between two ports (also called connection-oriented
service), with notification of delivery or nondelivery.
class 2. Connectionless service between ports with
notification of delivery or nondelivery.
class 3. Connectionless service between ports without
notification of delivery. Other than notification, the
transmission and routing of class 3 frames is the same
as class 2 frames.
class of service. A specified set of delivery
characteristics and attributes for frame delivery.
CMI. Control message interface.
comma. A unique pattern (either 1100000 or 0011111)
used in 8B/10B encoding to specify character alignment
within a data stream. See also K28.5.
CPLD. Complex programmable logic device.
community (SNMP). A relationship between an SNMP
agent and a set of SNMP managers that defines
authentication, access control, and proxy characteristics.
CPU. See central processing unit.
CRC. See cyclic redundancy check.
credit. When applied to a switch, the maximum
number of receive buffers provided by an F_port or
FL_port to its attached N_port or NL_port, respectively,
such that the N_port or NL_port may transmit frames
without over-running the F_port or FL_port.
cut-through. A switching technique that allows the
route for a frame to be selected as soon as the
destination address is received. See also route.
cyclic redundancy check (CRC). A check for
transmission errors included in every data frame.
data word. A type of transmission word that occurs
within frames. The frame header, data field, and CRC
all consist of data words. See also frame, ordered set,
transmission word.
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IBM TotalStorage
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SAN Fibre Channel Switch: 3534 Model F08 Installation Guide