A fundamental goal of data-center networking is to efficiently interconnect a large number of servers with low equipment cost while keeping high network bandwidth. Some server-centric data center networking structures are proposed to tackle the performance bottleneck and the extensibility problems that the traditional tree-based networking schemes are born with. Shipping-container-based data centers are introduced as building blocks for constructing mega-data centers. However, it is a challenge how to interconnect those containers to make sure that the network among the containers has both high scalability and high performance. As a new server-centric network architecture, BCube is able to interconnect thousands of servers into a container and provide high bandwidth for typical traffic patterns. This paper presents a networking architecture among containers called MDCent, which is based on BCube to interconnect servers inside a container. MDCent makes the network among containers have both high scalability and performance on condition that each container makes use of a lot of unused up-link ports and has a fixed degree.