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ANYCAST IMPLEMENTATION IN SDN
© 2010 Taylor & Francis Group, LLC
which can be obtained by the counters of flow table entries in the OFA
switches [26] as specified in “Preliminaries of SDN and OpenFlow,”
and thus can be captured by the anycast controller through the
OpenFlow protocol between the controller and the switches.
In the design of the anycast controller, we also adopt the Floyd-
Warshall algorithm [30] to perform routing strategies based on the
link loads, where the difference from the routing scheme based on
the hop counts is that the links in the network topology are weighted
with the loads. Algorithm 1 shows the calculation of the path using
the routing strategy based on link loads.
Algorithm 1: e calculation of the path based on li ...