27.7.3 The Flow Class

The class QueueMonitor/ED/Flow is used by the flow monitor for containing per-flow counters. As a subclass of QueueMonitor, it inherits the standard counters for arrivals, departures, and drops, both in packets and bytes. In addition, because each flow is typically identified by some combination of the packet source, destination, and flow identifier fields, these objects contain such fields. Its OTcl interface contains only bound variables:

rX src
_ & source address on packets for this flow
dst
_ & destination address on packets for this flow
flowid
_ & flow id on packets for this flow

Note that packets may be mapped to flows (by classifiers) using criteria other than a src/dst/flowid triple. In such circumstances, only those fields actually used by the classifier in performing the packet-flow mapping should be considered reliable.