HP StorageWorks Fabric OS 5.X Master Glossary (AA-RW7NA-TE, September 2005)

transmission word A group of four transmission characters.
See also transmission character.
trap (SNMP) The message sent by an SNMP agent to inform the SNMP management station
of a critical error.
See also SNMP.
trunking In Fi bre Channel technology, a feature that enables distribution of trafficover
the combined bandwidth of up to four ISLs between adjacent swi tches, while
preserving in-order delivery.
trunking g roup A set of up to four trunked ISL s for HP StorageWorks SAN Switch 2/8–EL,
2/8V, 2/16, 2/16V, 2/32, Core Switch 2/64, and SAN Director 2/128; a
set of up to eight trunked ISLs for HP StorageWorks SAN Switch 4/32 and
4/256 SAN Director .
trunking ports The por ts in a set of trunked ISLs.
TS Time Server. An intelligent entity in a network that enables all nodes in the
network to m a intain a common time base. It provides the time values required
to ma nage expiration timers.
TTL Time-to-live. The number of seconds an entry exists in cache before it expires.
tunneling A technique for enabling t wo networks to communicate when the source and
destination hosts are both o n the same type of network but are connected by
a different type of network.
TX T ransmit. An abbreviation for the communications term transmit.
See also RX.
UDP User Datagram Protocol. A protocol that runs on top of IP and provides port
multiplexing for upper-level protocols.
UL Underwriters Laboratories. An independent, not-for-profit, product-safety testing
and certification organization.
ULP Upper-level protocol. A protocol that runs on top of Fibre Channel. Typical
upper-level protocols are SCSI, IP, H IPPI, and IPI.
ULP_TOV Upper-level protocol timeout value. The minimum time that a SCSI ULP process
waits for SCSI status before initiating ULP recovery.
unicast The transmission of da ta from a single source to a single destination.
See also broadcast and multicast.
U_Port Universal por t. A switch por t that can operate as a G_Port, E_Port, F_Port, or
FL_Port. A port i s defined as a U_Por t when it is not connected or has not yet
assumed a specificfunctioninthefabric.
UTC Universal Time Conversion. Also called Coordinated Universal Time, which is
an international standard of time. UTC is 8 hours behind Pacific Standard Time
and5hoursbehindEasternStandardTime.
See also GMT.
WAN Wide area network. A communications network that covers a wide geographic
area, such a s a state o r a country.
See also LAN and MAN .
WAN_TOV Wide area net work timeout value.
watchdog A software daemon that m onitors Fabric OS modules on the kernel.
Fabric OS 5.x master glossary
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