Description: This MIB module defines objects that describe the a set of
metrics used to measure the quality of a IP CBR traffic flow. An
IP CBR traffic flow consists of a stream of IP datagrams sent
from one application to another with a constant packet rate or
bit rate.

GLOSSARY
============

CBR - Constant Bit Rate.

Delay Factor - the maximum observed value of the flow rate
    imbalance over a measurement interval.

DF - Delay Factor.

Flow Monitor - a hardware or software entity that classifies
    traffic flows, collects flow data, and periodically
    computes flow metrics.

Flow Metric - a measurement that reflects the quality of a
    traffic flow.

Measurement Interval - the length of time over which a flow
    monitor collects data related to a traffic flow, after which
    the flow monitor computes flow metrics using the collected
    data.

Media Rate - the effective bit rate of the media content
    carried by a traffic flow.

Media Rate Variation - a measure of loss (in bytes):

                 N
           RT - sum [Si]
                i=1
    MRV = ---------------
                 RT

    where R is the nominal media rate, T is the measurement
    interval, Si is the size of packet[i] received during the
    measurement interval, and N is the number of media packets
    received during the measurement interval.

MR - Media Rate.

MRV - Media Rate Variation.

Traffic Flow - a unidirectional stream of packets conforming to
    a classifier.  For example, packets having a particular 
    source IP address, destination IP address, protocol type,
    source port number, and destination port number.

VB - Virtual Buffer.

Virtual Buffer - a virtual buffer is a construct used to
    simulate a real buffer used by a media application for the
    purpose of storing media packets until the the application
    can render their content.