Software‐defined networking (SDN) acts as a centralized management unit, especially in a network with devices that operate under the transport layer of the OSI model. However, when a network with layer 7 middleboxes (MBs) is considered, current SDNs exhibit limitations. As such, to achieve a real‐centralized management unit, a new architecture is required that decouples the data and control planes of all network devices. In this report, we propose such a complementary architecture to the current SDN in which SDN‐enabled MBs are included along with contemporary SDN‐enabled switches. The management unit of this architecture improves network performance and reduces routing cost by considering the status of the MBs during flow forwarding. This unit consists of the following two parts: an SDN controller (SDNC) and a middlebox controller (MBC). The latter selects the best MBs for each flow and the former determines the best path according to its routing algorithm and provides information via the MBC. The results show that the proposed architecture improved performance because the utilization of all network devices including MBs is manageable.

中文翻译：

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走向软件定义网络中可管理的中间盒

软件定义网络（SDN）充当集中管理单元，尤其是在具有在OSI模型的传输层下运行的设备的网络中。但是，当考虑具有第7层中间盒（MB）的网络时，当前的SDN表现出局限性。因此，要实现真正集中的管理单元，就需要一种新的体系结构，该体系结构应将所有网络设备的数据和控制平面分离。在本报告中，我们提出了一种与当前SDN互补的体系结构，其中包括了支持SDN的MB和现代SDN启用的交换机。通过考虑流转发过程中MB的状态，此体系结构的管理单元可提高网络性能并降低路由成本。该单元由以下两个部分组成：SDN控制器（SDNC）和中间盒控制器（MBC）。后者为每个流选择最佳MB，而前者根据其路由算法确定最佳路径，并通过MBC提供信息。结果表明，由于包括MB在内的所有网络设备的利用率都是可管理的，因此所提出的体系结构提高了性能。