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QOS ISSUES IN OPENFLOW/SDN
© 2010 Taylor & Francis Group, LLC
To avoid excessive computational and storage overhead for a
controller in a large network, an additional adaptive flow aggrega-
tor (AFA) must be introduced. Instead of the controller computing
resource allocation for each flow, the AFA will categorize flows into
groups and will reserve resources based on each group. is is to be
noted because all traffic does not require per-flow isolation. ey only
need resource allocation for the aggregated flow.
As shown in Refs. [6] and [7], QoS routing has a significant
effect on the overall throughput of the network. Because the major
portion of Internet traffic is composed of the best-effort traffic, an
efficient routing algorithm that optimizes QoS must ...