IBM F16, Руководство пользователя

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ARP. See Address Resolution Protocol .
ASIC. See application-specific integrated circuit .
asynchronous transfer mode (ATM). A broadband
technology for transmitting data over local area
networks (LANs) or wide area networks (WANs), based
on relaying cells of fixed size. Provides any-to-any
connectivity, and nodes can transmit simultaneously.
ATM. See asynchronous transfer mode .
bandwidth. (1) The total transmission capacity of a
cable, link, or system. Usually measured in bits per
second (bps). (2) The range of transmission frequencies
available to a network. See also
throughput .
basic input/output system (BIOS). The personal
computer code that controls basic hardware operations,
such as interactions with diskette drives, hard disk
drives, and the keyboard.
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 (BER). 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 on which the 2109 Model F16 is based.
British thermal unit (BTU). A measurement of heat
produced in one hour.
broadcast. The transmission of data from a single
source to all devices in the fabric, regardless of zoning.
See also
multicast and unicast .
BTU. See British thermal unit .
buffer-to-buffer credit (BB_credit). Used to
determine how many frames can be sent to a recipient
when buffer-to-buffer flow control is in use. See also
buffer-to-buffer flow control and 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 .
cascading. The process of connecting two or more
Fibre Channel hubs or switches together to increase the
number of ports or extend distances. See also
fabric
and 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, which provides notification of delivery or
nondelivery between two expansion ports (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 identical to
that of class 2 frames.
class of service. A specified set of delivery
characteristics and attributes for frame delivery.
CLI. See command line interface .
CMI. See 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 .
command line interface (CLI). Interface that depends
entirely on the use of commands, such as through
Telnet or simple network management protocol (SNMP),
and does not involve a graphical user interface.
community (SNMP). A relationship between a simple
network management protocol (SNMP) agent and a set
of SNMP managers that defines authentication, access
control, and proxy characteristics.
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IBM TotalStorage SAN Switch: 2109 Model F16 User’s Guide