A novel framework, Medium-Term Disruption Tolerant Software Defined Network (MDT-SDN), is proposed to handle medium-term disruptions of the order 10 seconds to 6 minutes. Such medium-term disruptions are crucial for the next generation wireless networks that use TCP/IP protocol stack, where the existing disruption tolerant approaches may under-perform due to resource constraints. MDT-SDN enables network control with an additional STORE action which exploits the nodes’ memory for buffering packets within the TCP/IP stack during link disruptions and forwards them as the links become alive. First, we model the network with medium-term disruptions using temporal graphs and design an Earliest Arrival Path with Minimal Storage Time (EAPMST) controller algorithm to demonstrate the MDT-SDN framework. The framework is realized in a software defined wireless mesh network testbed, using in-band control, involving mobile nodes with three mobility models: ( ${i}$ ) stationary nodes, (ii) group mobility, and (iii) random mobility. Experimental results with four application protocols justify the efficacy of MDT-SDN in providing storage control and additional performance benefits. MDT-SDN along with EAPMST improves the throughput beyond 25% with random mobility model and is capable of carrying packets and maintaining sessions during medium-term disruptions using the existing TCP/IP stack. The use of EAPMST reduces packets’ buffering time by 24.45% in group mobility while the buffering time increases in random mobility by 5.82%. However, EAPMST significantly reduces the buffer occupancy by 60.28% and 44.49% for group and random mobility, respectively.

中文翻译：

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用于无线 TCP/IP 网络的中期中断容忍 SDN

提出了一种新的框架，即容忍中期中断的软件定义网络 (MDT-SDN)，以处理 10 秒到 6 分钟的中期中断。这种中期中断对于使用 TCP/IP 协议栈的下一代无线网络至关重要，现有的中断容忍方法可能由于资源限制而表现不佳。MDT-SDN 通过额外的 STORE 操作实现网络控制，该操作利用节点的内存在链路中断期间缓冲 TCP/IP 堆栈中的数据包，并在链路变为活动状态时转发它们。首先，我们使用时间图对具有中期中断的网络进行建模，并设计具有最小存储时间的最早到达路径 (EAPMST) 控制器算法来演示 MDT-SDN 框架。该框架是在软件定义的无线网状网络测试台中实现的，使用带内控制，涉及具有三个移动模型的移动节点：(${i}$) 固定节点，(ii) 组移动，和 (iii) 随机移动。四种应用协议的实验结果证明了 MDT-SDN 在提供存储控制和额外性能优势方面的功效。MDT-SDN 与 EAPMST 一起使用随机移动模型将吞吐量提高了 25% 以上，并且能够使用现有的 TCP/IP 堆栈在中期中断期间传输数据包和维持会话。EAPMST 的使用使分组移动中的数据包缓冲时间减少了 24.45%，而随机移动中的缓冲时间增加了 5.82%。然而，EAPMST 显着降低了组和随机移动性的缓冲区占用率分别为 60.28% 和 44.49%。