With the growth of network traffic volume, link congestion cannot be avoided efficiently with conventional routing protocols. By utilizing the single shortestpath routing algorithm from link state advertisement information, standard routing protocols lack of global awareness and are difficult to be modified in a traditional network environment. Recently, software-defined network (SDN) provided innovative architecture for researchers to program their own network protocols. With SDN, we can divert heavy traffic to multiple paths in order to resolve link congestion. Furthermore, certain network traffics come in periodic fashion such as peak hours at working days so that we can leverage forecasting for resource management to improve its performance. In this paper, we propose a proactive multipath routing with a predictive mechanism (PMRP) to achieve high-performance congestion resolution. PMRP has two main concepts: (a) a proactive mechanism where PMRP deploys M/M/1 queue and traffic statistics to simulate weighted delay for possible combinations of multipaths placement of all subnet pairs, and leverage genetic algorithm for accelerating selection of optimized solution, and (b) a predictive mechanism whereby PMRP uses exponential smoothing for demand traffic volumes and variance predictions. Experimental results show a 49% reduction in average delay as compared with single shortest routing, and a 16% reduction in average delay compared with utilization & topology-aware multipath routing (UTAMP). With the predictive mechanism, PMRP can decrease an additional 20% average delay. Furthermore, PMRP reduces 93% of flow table usage on average as compared with UTAMP.links. Furthermore, periodically updating the link weights provided by link state advertisement is insensitive for network congestions. In addition to congestion resolution, there are no forecasting functions for resource management. The network pattern also has locality phenomenon such as daily rush hours so that we can leverage it for bandwidth allocation in routing mechanism. However, it is difficult to modify standard routing protocols in conventional distributed network architecture, and it is impossible to replace every individual commodity router to provide better congestion control algorithms.Recent work on software-defined network (SDN) architecture 1 separates the control plane from data plane and provides programmable Application Programming Interface (API) for provisioning and management. With a centralized controller, a global view of network topology with status can be obtained, and researchers could implement network protocols easily in the SDN environment. However, flow tables in SDN switches are limited resources, and care has to be taken with use of flow entries. If we design a routing management mechanism according to host pairs, the number of flow entries will increase dramatically and will rapidly exceed the limits of the hardware. One would consequently like to manage the flows based on subnet pairs for better flow table utilization. For exa...