Technical data

Brocade SilkWorm 4100 Hardware Reference Manual Glossary-31
Publication Number: 53-0000563-02
U
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.
UL Underwriter's Laboratories. A product-safety testing and certification organization; independent, not-
for-profit.
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.
V
W
WAN Wide area network.
WAN_TOV Wide area network timeout value.
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.
workstation A computer used to access and manage the fabric. Also referred to as a “management station” or “host.”
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.