Abstract: For the overload problem of single controller in Software Defined Network (SDN), a game theory based master controller reselection mechanism-GAME-System Model (GAME-SM) was proposed. Firstly, the problem of switch migration constrained by resource was translated into maximizing revenue problem of zero sum game, and the GAME-SM mechanism was proposed. Secondly, the upper and lower thresholds of the controller load were set to determine the trigger conditions of the game, and the controller whose load reached the upper limit invited the neighboring controllers to participate in the game as game players. Finally, the game strategy was designed based on the zero sum game to maximize the revenue of each participant, and the master controller was reselected by the repeated game with the change of utility degree, and the load balance of the whole system was realized eventually. The simulation results show that the proposed mechanism can significantly improve the controller load balance, and the controller response time is reduced by 50% compared with Distributed-CoNTroLler (D-CNTL).

Key words: Software Defined Network (SDN), switch migration, load balance, game theory, master controller reselection

摘要： 针对软件定义网络（SDN）中单一控制器容易发生过载的问题，提出了一种基于博弈论的主控制器重选机制——博弈系统模型（GAME-SM）。首先，把资源限定下的交换机迁移问题等效为零和博弈最大化收益问题，并提出了GAME-SM机制；其次，设置控制器负载上下限阈值来确定博弈触发的条件，达到负载上限的控制器邀请邻近的其他控制器作为博弈者参与博弈；最后，基于零和博弈最大化每个参与者的收益来设计博弈策略，使用利用度的改变进行反复博弈来重选主控制器，最终实现整个系统的负载均衡。仿真结果表明该机制能够明显改善控制器负载平衡状况，且与静态分布式控制器（D-CNTL）相比，控制器响应时间减少了50%。

关键词: 软件定义网络, 交换机迁移, 负载均衡, 博弈论, 主控制器重选