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LANGUAGE AND PROGRAMMING IN SDN/OPENFLOW
© 2010 Taylor & Francis Group, LLC
3. Combining metrics: A good solution is to combine several fac-
tors (parameters) and use them for evaluation. However, the
question of how to combine different criteria or come up with
a good solution remains the same.
4. Computational complexity: Another great problem is the opti-
mization of each factor in consideration. is poses an non-
deterministic polynomial-time hard (NP-hard) problem for
each metric. Some of these factors/metrics include, but are
not limited to, the availability of resources, how fair the dis-
tribution of the resources is, and the latency and congestion in
different channels.
5. Design space size: ere are several options to implement the