6760 ServerNet/DA Manual

Glossary
6760 ServerNet/DA Manual—424879-003
Glossary-98
topology branch
topology branch. A processor enclosure and the I/O enclosures attached to it.
total harmonic distortion (THD). The ratio, expressed in percent, of the root mean square
(rms) value for all harmonics present in the output of a power source to the total rms
voltage at the output, for a pure sine-wave output. The lower the THD, the better the
power source.
Total Information Manager (TIM). The software package for viewing and searching HP
NonStop™ S-series hardware and software documentation. You can use TIM software
while your computer is connected to a network or on a stand-alone workstation.
Transaction Management Facility (TMF) subsystem. The major component of the HP
NonStop™ Transaction Manager product, which protects databases in online
transaction processing (OLTP) environments. To furnish this service, the TMF
subsystem manages database transactions, keeps track of database activity through
audit trails, and provides database recovery methods. Formerly called Transaction
Monitoring Facility (TMF). See also HP NonStop™ Transaction Manager
.
transformer. Equipment used to step up or step down alternating-current (ac) voltage to
meet the specific requirements of the load. A transformer also provides isolation and
noise-attenuation properties.
transient. A short-duration, high-amplitude impulse that is imposed upon the normal voltage
or current.
translation lookaside buffer (TLB). A buffer for handling virtual addresses.
Transmission Control Protocol (TCP). A connection-oriented protocol that provides for the
reliable exchange of data between a sending and a receiving system. TCP implements
functions corresponding to the Open Systems Interconnection (OSI) reference model
Layer 4, the transport layer.
Transmission Control Protocol/Internet Protocol (TCP/IP). A set of layered
communication protocols for connecting workstations and larger systems in both local
area networks (LANs) and wide area networks (WANs). See also HP NonStop™
TCP/IP and Parallel Library TCP/IP.
tri-star topology. A network topology that uses up to three HP NonStop™ Cluster Switches
for each external fabric. External routing is implemented between the three star groups
of a ServerNet cluster. (A star group consists of the eight nodes attached to one set of
cluster switches.) The star groups are joined by two-lane link
s. Introduced with the
G06.14 release version update (RVU) of the HP NonStop ServerNet Cluster product,
the tri-star topology supports up to 24 nodes. See also split-star topology.
Trivial File Transfer Protocol (TFTP). A protocol defined by Request for Comments (RFC)
1350. TFTP is used as a data link control (DLC) and diagnostic task.
TRSA. See Token-Ring ServerNet adapter (TRSA).