Glossary
212 Avaya P460 Reference Guide
Trap
Message sent by an SNMP agent to an NMS, console, or terminal to indicate the
occurrence of a significant event, such as a specifically defined condition or a
threshold that was reached. Similar to an alarm.
Tree View
A resizeable window containing a hierarchical representation of the modules and
ports of the device.
UDP
User Datagram Protocol. Connectionless transport layer protocol in the TCP/IP
protocol stack. UDP is a simple protocol that exchanges datagrams without
acknowledgments or guaranteed delivery, requiring that error processing and
retransmission be handled by other protocols.
UNI
User-Network Interface. The interface - defined as a set of protocols and traffic
characteristics, such as cell structure - between the user and the ATM network.
Unicast
A single packet sent to a single network destination.
VBR
Variable Bit Rate. VBR is a QoS class for ATM networks. It is subdivided into a real
time (RT) class and non-real time (NRT) class. VBR-RT is used for connections in
which there is a fixed timing relationship between samples. VBR-NRT is used for
connections in which there is no fixed timing relationship between samples, but that
still need a guaranteed QoS.
VC
Refer to Virtual Channel on page 213, Virtual Circuit on page 213, and Virtual
Connection on page 213.
VCI
Virtual Channel Identifier. A 16 bit value in the ATM cell header that provides a
unique identifier for the Virtual Channel (VC) within a Virtual Path that carries a
particular cell.
VIDP
VLAN Information Distribution Protocol. VIDP is a proprietary Avaya protocol
running between Avaya P110 Device and Avaya M770 Device agents. A station’s
VLAN information is distributed to all agents in order to use this information
throughout the network.
