在低功耗有损网络(low power and lossy networks)中,现有的移动性支持路由算法存在控制消息冗余,应用场景不具有普适应,网络丢包率和移动节点能耗较高等问题.针对这些问题,提出一种移动场景下的节点高效寻路RPL路由算法(efficient path...在低功耗有损网络(low power and lossy networks)中,现有的移动性支持路由算法存在控制消息冗余,应用场景不具有普适应,网络丢包率和移动节点能耗较高等问题.针对这些问题,提出一种移动场景下的节点高效寻路RPL路由算法(efficient pathfinding RPL routing algorithm for nodes in mobile scenarios,MSE-RPL).该算法提出的优化思路如下:首先,精简了移动节点的控制消息,并采用自适应黑名单机制建立备选父节点集,从而降低了移动节点的能耗;其次,基于移动节点的移动速度和方向,从备选父节点集中选择移出通信范围预估时间最短的节点作为最优父节点,不但适用于随机移动场景,还降低了平均端到端时延;最后,在链路中断前,利用DIS计时器及时通告DIS消息以快速重构拓扑,降低了丢包率.仿真结果表明,MSE-RPL算法在平均端到端时延、移动节点能耗、丢包率等性能指标方面均有明显改善.展开更多
Adopting the borrowed address algorithm can decrease the orphan nodes in ZigBee networks that use distributed address assignment mechanism （DAAM）. The existing borrowed address algorithms can increase the success ra...Adopting the borrowed address algorithm can decrease the orphan nodes in ZigBee networks that use distributed address assignment mechanism （DAAM）. The existing borrowed address algorithms can increase the success rate of address assignment, but they have defects such as greater cost of overhead and time in founding network caused by breaking topology. To solve such problems, we propose an more efficient distributed borrowed address assignment algorithm based on topology maintenance （A2BTM） that has a topology maintenance function. It borrows address firstly from the offspring nodes in the same branch for the orphan nodes and replies distributed the request of the borrowed address message immediately, to maintain the network topology and decrease the overhead and time spent on the mechanism of borrowed address. Theoretical and simulation analyses manifest that AZBTM algorithm outperforms DAAM and its improved algorithms in terms of the overhead and time spent in founding network, on the premise of keeping a higher success rate of address assignment. Furthermore, A2BTM can lessen the influence from detour phenomenon efficiently.展开更多
To improve the performance of transmission by reducing the number of transmission and network overhead of wireless single-hop networks, this paper presents a high efficient multipacket decoding approach for network co...To improve the performance of transmission by reducing the number of transmission and network overhead of wireless single-hop networks, this paper presents a high efficient multipacket decoding approach for network coding （EMDNC） in wireless networks according to the idea of encoding packets which cannot be decoded and are stored in buffer by receiving nodes, the lost packets can be recovered from these encoded packets. Compared with the network coding wireless broadcasting retransmission （NCWBR）, EMDNC can improve the efficiency of decoding and reduce the number of retransmission and transmission delay. Simulation results reveal that EMDNC can effectively reduce the number of retransmission and network overhead.展开更多
文摘在低功耗有损网络(low power and lossy networks)中,现有的移动性支持路由算法存在控制消息冗余,应用场景不具有普适应,网络丢包率和移动节点能耗较高等问题.针对这些问题,提出一种移动场景下的节点高效寻路RPL路由算法(efficient pathfinding RPL routing algorithm for nodes in mobile scenarios,MSE-RPL).该算法提出的优化思路如下:首先,精简了移动节点的控制消息,并采用自适应黑名单机制建立备选父节点集,从而降低了移动节点的能耗;其次,基于移动节点的移动速度和方向,从备选父节点集中选择移出通信范围预估时间最短的节点作为最优父节点,不但适用于随机移动场景,还降低了平均端到端时延;最后,在链路中断前,利用DIS计时器及时通告DIS消息以快速重构拓扑,降低了丢包率.仿真结果表明,MSE-RPL算法在平均端到端时延、移动节点能耗、丢包率等性能指标方面均有明显改善.
基金supported by Natural Science Foundation Project of CQ CSTC (2012jjA40040)the National Natural Science Foundation of China (60972068)
文摘Adopting the borrowed address algorithm can decrease the orphan nodes in ZigBee networks that use distributed address assignment mechanism （DAAM）. The existing borrowed address algorithms can increase the success rate of address assignment, but they have defects such as greater cost of overhead and time in founding network caused by breaking topology. To solve such problems, we propose an more efficient distributed borrowed address assignment algorithm based on topology maintenance （A2BTM） that has a topology maintenance function. It borrows address firstly from the offspring nodes in the same branch for the orphan nodes and replies distributed the request of the borrowed address message immediately, to maintain the network topology and decrease the overhead and time spent on the mechanism of borrowed address. Theoretical and simulation analyses manifest that AZBTM algorithm outperforms DAAM and its improved algorithms in terms of the overhead and time spent in founding network, on the premise of keeping a higher success rate of address assignment. Furthermore, A2BTM can lessen the influence from detour phenomenon efficiently.
基金supported by the Natural Science Foundation Project of CQ CSTC (2012jjA40040)the National Natural Science Foundation of China (60972068)
文摘To improve the performance of transmission by reducing the number of transmission and network overhead of wireless single-hop networks, this paper presents a high efficient multipacket decoding approach for network coding （EMDNC） in wireless networks according to the idea of encoding packets which cannot be decoded and are stored in buffer by receiving nodes, the lost packets can be recovered from these encoded packets. Compared with the network coding wireless broadcasting retransmission （NCWBR）, EMDNC can improve the efficiency of decoding and reduce the number of retransmission and transmission delay. Simulation results reveal that EMDNC can effectively reduce the number of retransmission and network overhead.
