Game model for switch migrations in software-defined network

Several reported studies have focussed particular interest on the elastic control via OpenFlow (OF) switch migrations in software-defined networks to avoid uneven load distributions among controllers. However, it is not clear which switch should be migrated and where it will be moved. A paradigm that the heavy controller tries to migrate its switches, and other light controllers compete for the migrated switches, is designed. Then, taking light controllers as the game players and OF switches as commodities, a zero-sum game model is exploited, to emulate the competitions for migrated switches among light controllers. This model first chooses a switch for migration by a heavy controller (called the game sponsor) which invites its light neighbours as game players to formulate the local game domain (GD). Secondly, the process of game-play in one GD is designed based on the constraints of the zero-sum game. Note that several non-overlapped GDs could co-exist over the network so that the game-plays could be calculated in the concurrent way. The results are corroborated by several numerical experiments.