iTP Secure WebServer Operator Messages Manual

Glossary
iTP Secure WebServer Operator Messages Manual—429507-002
Glossary-4
packet
packet. The unit of data sent across a packet-switching network. While some Internet
literature uses it to refer specifically to data sent across a physical network, other
literature views the Internet as a packet-switching network and describes IP datagrams
as packets.
PATHMON. The central controlling process for a NonStop TS/MP application.
Pathway. The former name of NonStop TS/MP, a product providing transaction services for
persistent, scalable, transaction-processing applications.
physical layer. Layer 1 in the OSI Reference Model. This layer establishes the actual
physical connection between the network and the computer equipment. Protocols at
the Physical Layer include rules for the transmission of bits across the physical
medium and rules for connectors and wiring.
process. A running entity that is managed by the operating system, as opposed to a
program, which is a collection of code and data. When a program is taken from a file
on a disk and run in a processor, the running entity is called a process.
protocol. A formal description of the message formats and rules two or more machines
must follow to exchange messages. Protocols can describe low-level details of
machine-to-machine interfaces (for example, the order in which the bits from a byte are
sent across a wire) or high-level exchanges between application programs (for
example, the way in which two programs transfer a file across the Internet). Most
protocols include both intuitive descriptions of the expected interactions and more
formal specifications using finite state-machine models.
QIO subsystem. A product that provides buffers and control blocks for protocol processes,
including TCP/IP, TLAM, and NonStop IPX/SPX running on the same processor.
Request for Comments (RFC). The name of a series of notes that contain surveys,
measurements, ideas, techniques, and observations, along with proposed and
accepted Internet protocol standards. RFCs are edited but not referenced. They are
available across the Internet.
RFC. See Request for Comments (RFC)
Secure Sockets Layer (SSL). A protocol for private communication on the World Wide
Web and authentication of a web server by a web client.
server. A process or set of processes that satisfy requests from web clients in a client-
server environment.
server class. A grouping of duplicate copies of a single server program, all of which
execute the same object program.
server process. A process that implements requests for an application and returns replies
to the requester.