Technical data

Trivial File Transfer Protocol (TFTP)
The Internet protocol for file transfer with minimal capability and minimal
overhead. The simple design of the facility is intended for use in application
environments that do not require complex interactions among clients and servers.
TFTP is a simple service running on top of UDP, using timeout and retransmission
to ensure that data arrives. The sending side transmits a 512-byte, fixed-size
file, and awaits an acknowledgment for each block before sending the next. The
receiver acknowledges each block. See also File Transfer Protocol.
TTL
See time to live.
tunneling
The encapsulation of protocol A within protocol B such that A t
reats B as though B
were a Network Interface layer. Used to get data between admin
istrative domains
that use a protocol not supported by the internet connecting
those domains.
UAF
See user authorization file.
UCP
See Management Control Program.
Management Control Program
The Compaq TCP/IP Services for OpenVMS network management control software;
includes a command-line interface.
UDP
See User Datagram Protocol.
UID
See user identification.
UNIX-style file system
An OpenVMS organization of files based on the UNIX operating system. Also
known as a container file system.
UNIX-to-UNIX Copy Program (UUCP)
A program that allows one UNIX system to copy files to or from another UNIX
system.
upline dumping
A TFTP server function allowing a TFTP client to transfer data or a program image
to the TFTP server’s public directories. The opposite function of downline loading.
user authorization file (UAF)
An OpenVMS file that contains account names and their associated attributes.
User Datagram Protocol (UDP)
An Internet transport protocol. A connectionless, unreliable Transport layer
protocol for the exchange of requests and replies between networked hosts. UDP,
like TCP, uses IP for message delivery from one host to another; however, unlike
TCP, UDP provides for exchange of datagrams without acknowledgments or
guaranteed delivery of data. Each UDP message contains the data sent by a user
process, a destination port number, and a source port number.
user identification (UID)
A unique number that identifies a user of a UNIX system. The number along with
an associated group identification number (GID) determines file access privileges.
UID also tracks accounting statistics and other collected information.
Glossary–47