面向异构业务的基于数据包优先权的组播算法

Priority-Oriented Multicast Transmission Algorithm for Heterogeneous Traffic in WSNs

由于基于IEEE 802.15.4标准的无线传感网络WSNs(Wireless Sensor Networks)未引用业务优先机制,确保异构业务的服务质量Qo S(Quality of Service)存在挑战。为此,提出面向异构业务的基于数据包优先权的组播算法POMT(PriorityOriented Multicast Transmission algorithm for heterogeneous traffic)。POMT算法通过减少队列、媒体接入控制MAC(Medium Access Control)和传输时延,减少端到端传输时延,并为优先数据包提供可靠的组播传输。基于异构业务类型,POMT算法选择不同的信道竞争窗口尺寸。此外,POMT算法利用两类确认包和重传机制,保证数据包传输的可靠性。实验数据表明,相比于传统的CSMA/CA策略,POMT算法控制了端到端传输时延和提高了数据包传递率,并降低了碰撞概率。

To ensure quality of service（ QoS） for heterogeneous traffic in IEEE 802.15.4 based wireless sensor networks（ WSNs） is a challenging task since no traffic prioritization mechanism is defined in such WSNs. Therefore,Priority-oriented Multicast Transmission algorithm for heterogeneous traffic（ POMT） is proposed in this paper. POMT algorithm focuses on reducing queuing,MAC and transmission delay to ensure shorter end-to-end delay,and provide reliable multicast transmissions for priority packets. For different classes of traffic,POMT chose different contention window（ CW） size. In addition,POMT enables two ACK packets and retransmission to ensure reliability. Simulation results show that MS-MAC outperforms CMSA/CA,in terms of end-to-end delay and packet delivery ratio and collision probability.