Introduction to Networking for NonStop S-Series Servers

Glossary
Introduction to Networking for HP NonStop S-Series Servers—520670-005
Glossary-22
system services control point (SSCP)
system services control point (SSCP). An IBM Systems Network Architecture (SNA)
network entity residing in a host node and providing services for control of network
resources.
Systems Network Architecture (SNA). The IBM communications model that describes the
logical structure, formats, protocols, and operational sequences for transmitting
information units through, and controlling the configuration and operation of, networks.
TCP/IP. See Transmission Control Protocol/Internet Protocol (TCP/IP).
terminal control process (TCP). A process used for terminal management and transaction
control, provided by HP as part of the Pathway/TS product.
token-bus network. A network in which computers are connected on a bus (as opposed to
a ring or star shape) and in which the right to transmit data is defined by possession of
a special kind of data unit, called a token. Stations pass the token from one to the next
in logical order: for example, in order by station address.
token-ring network. A network in which computers are connected in a ring-shaped layout
(topology) and in which the right to transmit data is defined by possession of special
kind of data unit, called a token. A station that is finished transmitting or that does not
wish to transmit passes the token along to the adjacent station on the ring.
topology. The geometric layout of a network. Examples of network topologies are ring
(nodes arranged in a circle), star (one node in the middle with connections to each of
the other nodes), bus (nodes arranged in a line), and mesh (nodes arranged in a
complex way, with multiple cross-connections between nodes).
Transmission Control Protocol (TCP). The Internet standard transport-level protocol that
provides the reliable, full-duplex stream service on which many application protocols
depend. TCP allows a process on one machine to send a stream of data to a process
on another. It is connection-oriented, in the sense that before transmitting data
participants must establish a connection. Software implementing TCP usually uses the
Internet Protocol (IP) to transmit information across the Internet. The IP suite is often
referred to as TCP/IP because TCP is one of the two most fundamental protocols.
Transmission Control Protocol/Internet Protocol (TCP/IP). A set of layered
communications protocols for connecting workstations and larger systems. See also
Transmission Control Protocol (TCP).
transport class. A definition of the capabilities and responsibilities of an Open Systems
Interconnection (OSI) Transport Layer implementation, tailoring the functions of the
transport layer to the characteristics of an underlying network environment. For
example, different transport classes imply different levels of responsibility for error-
handling.
Transport Layer. Layer 4 of the Open Systems Interconnection (OSI) Reference Model,
responsible for reliable transfer of data between sending and receiving systems.
Transport classes determine the level of service; for example, if the underlying network