ATM Configuration and Management Manual

Glossary
ATM Configuration and Management Manual—522307-003
Glossary-24
Transmission Control Protocol/Internet Protocol
(TCP/IP)
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.
TSM package. See Compaq TSM package
UBR. See Unspecified Bit Rate (UBR).
UDP. See User Datagram Protocol (UDP).
UNI. See User-Network Interface (UNI).
Unspecified Bit Rate (UBR). An ATM service type in which the ATM network makes a best
effort to meet the transmitter’s bandwidth requirements.
User Datagram Protocol (UDP). This protocol is part of the TCP/IP protocol suite and
provides a means for applications to access the connection less features of IP. UDP
operates at layer 4 of the OSI reference model and provides for the exchange of
datagrams without acknowledgments or guaranteed delivery.
User-Network Interface (UNI). An interface point between ATM end users and a private
ATM switch, or between a private ATM switch and the public carrier ATM network;
defined by physical and protocol specifications per ATM Forum UNI documents. The
standard adopted by the ATM Forum to define connections between users or end
stations and a local switch.
Virtual Channel (VC). A communications channel that provides for the sequential
unidirectional transport of ATM cells.
VCI. See Virtual Channel Identifier (VCI).
Virtual Channel Identifier (VCI). A unique numeric tag as defined by a 16 bit field in the
ATM cell header that identifies a VC, over which the cell is to travel.
Virtual Path (VP). A unidirectional logical association or bundle of VCs. unique numeric tag
as defined by a 16 bit field in the ATM cell header that identifies a VC, over which the
cell is to travel.
Virtual Path Identifier (VPI). An 8-bit field in the ATM cell header that indicates the VP over
which the cell should be routed.
VP. See Virtual Path (VP).
VPI. See Virtual Path Identifier (VPI).
WAN. See wide area network (WAN).