HP StorageWorks XPath OS 7.4.X Command Reference Guide (AA-RVHCC-TE, September 2005)

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TS Time Server.
TTL Time-to-live. The number of seconds an entry exists in cache before it expires.
tunneling A technique for enabling two networks to communicate when the source and destination hosts
are both on the same type of network but are connected by a different type of network.
TX Transmit.
U_Port Universal port. A switch port that can operate as a G_Port, E_Port, F_Port, or FL_Port. A port is
defined as a U_Port when it is not connected or has not yet assumed a specific function in the
fabric.
UDP User Datagram Protocol. A protocol that runs on top of IP and provides port multiplexing for
upper-level protocols.
ULP Upper-level protocol. The protocol that runs on top of Fibre Channel. Typical upper-level
protocols are SCSI, IP, HIPPI, and IPI.
ULP_TOV Upper-level timeout value. The minimum time that an SCSI ULP process waits for SCSI status
before initiating ULP recovery.
unicast The transmission of data from a single source to a single destination. See also broadcast,
multicast.
UTC Universal Time Conversion. Also known as Coordinated Universal Time, which is an
international standard of time. UTC is 8 hours behind Pacific Standard Time and 5 hours
behind Eastern Standard Time. See also GMT.
WAN Wide area network.
watchdog A software daemon that monitors Fabric OS modules on the kernel.
WDM Wavelength division multiplexer. Allows multiple wavelengths to be combined or filtered on a
single cable.
well-known address As it pertains to Fibre Channel technology, a logical address defined by Fibre Channel
standards as assigned to a specific function and stored on the switch.
WTV Write timeout value. Refers to an ELS field that appears in portLogDump command output.
WWN World wide name. An identifier that is unique worldwide. Each entity in a fabric has a
separate WWN.
X.25 A protocol that uses logical channels. X.25 allows high-quality communications between
computers and can accommodate noisy data communications through error-detection and
error-correction (retransmission) algorithms.
zone A set of devices and hosts attached to the same fabric and configured as being in the same
zone. Devices and hosts within the same zone have access to others in the zone but are not
visible to any outside the zone.
zone configuration A specified set of zones. Enabling a configuration enables all zones in that configuration. See
also defined zone configuration, enabled zone configuration.
zoning A feature in fabric switches or hubs that allows segmentation of a node by physical port,
name, or address.