Ad Hoc Probe是目前测量无线网络路径带宽的主要方法,由于发送探测分组数目固定,当负载较轻时,仅需要几组探测报文就能够获得正确的样本,所以限制了无线Ad Hoc网络的动态性。针对Ad Hoc Probe算法的不足,提出了AdHoc TP算法,一次发送三...Ad Hoc Probe是目前测量无线网络路径带宽的主要方法,由于发送探测分组数目固定,当负载较轻时,仅需要几组探测报文就能够获得正确的样本,所以限制了无线Ad Hoc网络的动态性。针对Ad Hoc Probe算法的不足,提出了AdHoc TP算法,一次发送三个报文,组成两个报文对,通过比较两个报文对的时间间隔和最小时延和提高样本的过滤速度,从而使测量速度更快。Qual Net仿真的结果表明,Ad Hoc TP算法能够正确地测量出有线/无线Ad Hoc混合网络的带宽,而且测量速度较快。展开更多
Sometimes user has the requirement to run a high bandwidth application over a low bandwidth network. But its implementation is not easy as the traditional network transmits data with only one path where its bandwidth ...Sometimes user has the requirement to run a high bandwidth application over a low bandwidth network. But its implementation is not easy as the traditional network transmits data with only one path where its bandwidth is lower than the demand. Although the current network technology like SDN has the ability to precisely control the data transmission in the network, but till now the standard openflow protocol does not support splitting one flow to multiple flows. In this paper, a flow splitting algorithm is proposed. The algorithm splits a data flow to multiple sub-flows by extending the openflow protocol. A multiple paths routing algorithm is also proposed to implement the multi-path parallel transmission in the paper. The algorithm selects multiple paths and minimizes the cost of transmission under the constraint of maximum delay and delay variance. The simulations show the algorithms can significantly improve the transmission performance.展开更多
In order to improve the transmission accuracy and efficiency of sensing and actuating signals in Internet of Things (loT) and ensure the system stability, an adaptive resource allocation algorithm is proposed, which...In order to improve the transmission accuracy and efficiency of sensing and actuating signals in Internet of Things (loT) and ensure the system stability, an adaptive resource allocation algorithm is proposed, which dynami- cally assigns the network bandwidth and priority among components according to their signals' frequency domain characteristics. A remote sensed and controlled unmanned ground vehicle (UGV) path tracking test-bed was devel- oped and multiple UGV's tracking error signals were measured in the simulation for performance evaluation. Results show that with the same network bandwidth constraints, the proposed algorithm can reduce,, the accumulated and maximum errors of UGV path tracking by over 60% compared with the conventional static algorithm.展开更多
文摘Ad Hoc Probe是目前测量无线网络路径带宽的主要方法,由于发送探测分组数目固定,当负载较轻时,仅需要几组探测报文就能够获得正确的样本,所以限制了无线Ad Hoc网络的动态性。针对Ad Hoc Probe算法的不足,提出了AdHoc TP算法,一次发送三个报文,组成两个报文对,通过比较两个报文对的时间间隔和最小时延和提高样本的过滤速度,从而使测量速度更快。Qual Net仿真的结果表明,Ad Hoc TP算法能够正确地测量出有线/无线Ad Hoc混合网络的带宽,而且测量速度较快。
基金supported by the National Science Foundation of China(No.61772385,No.61373040,No.61572370)
文摘Sometimes user has the requirement to run a high bandwidth application over a low bandwidth network. But its implementation is not easy as the traditional network transmits data with only one path where its bandwidth is lower than the demand. Although the current network technology like SDN has the ability to precisely control the data transmission in the network, but till now the standard openflow protocol does not support splitting one flow to multiple flows. In this paper, a flow splitting algorithm is proposed. The algorithm splits a data flow to multiple sub-flows by extending the openflow protocol. A multiple paths routing algorithm is also proposed to implement the multi-path parallel transmission in the paper. The algorithm selects multiple paths and minimizes the cost of transmission under the constraint of maximum delay and delay variance. The simulations show the algorithms can significantly improve the transmission performance.
基金Supported by Natural Science Foundation of Tianjin (No. 07JCZDJC05800)Science and Technology Supporting Plan of Tianjin (No. 09ZCKFGX29200)
文摘In order to improve the transmission accuracy and efficiency of sensing and actuating signals in Internet of Things (loT) and ensure the system stability, an adaptive resource allocation algorithm is proposed, which dynami- cally assigns the network bandwidth and priority among components according to their signals' frequency domain characteristics. A remote sensed and controlled unmanned ground vehicle (UGV) path tracking test-bed was devel- oped and multiple UGV's tracking error signals were measured in the simulation for performance evaluation. Results show that with the same network bandwidth constraints, the proposed algorithm can reduce,, the accumulated and maximum errors of UGV path tracking by over 60% compared with the conventional static algorithm.