Pair-nodes Selection Algorithm for PBS (Pairwise Broadcast Synchronization)

PBS(Pairwise Broadcast Synchronization)를 위한 노드 쌍 선택 알고리즘

Abstract

PBS(Pairwise Broadcast Synchronization) is a well-known synchronization scheme for WSN(Wireless Sensor Networks). As PBS needs the set of node-pairs for network-wide synchronization by over-hearing, GPA(Group-Wise Pair Selection Algorithm) was also proposed after PBS. However, GPA is complex and requires too many message transmissions, leading to much power consumption. Besides, GPA is not appropriate to topology change or mobile wireless sensor networks. So, we propose a new and energy-efficient pair-node selection algorithm for PBS. The proposed scheme's performance has been evaluated and compared with GPA by simulation. The results are shown to be better than GPA.

Fig. 1. Receiver-only synchronization [1].

Fig. 2. 멀티홉 네트워크 전체 동기화 과정 [5].

Fig. 3. Neighbor nodes to be overheard by two no-des(parent and child) at single hop.

Fig. 4. Neighbor nodes to be overheard by two nodes (parent and child) at multi-hop.

Fig. 5. Areas covered by pair-nodes according to the distance between pair-nodes.

Fig. 6. Covered areas and tree level.

Fig. 7. Covered areas and tree level in the proposed scheme.

Fig. 8. Tree Construction Algorithm proposed.

Fig. 9. Tree and backbone nodes constructed at the basic topology.

Fig. 10. Comparison of # MSG and Max_Depth of Trees constructed by two algorithms.

Fig. 11. Comparison of Max-Depth of Trees for two al-gorithms according to changing density.

Fig. 12. Comparison of‘# of Pair-node groups in both algorithms according to the # of nodes.

Table 1. Parameters for simulation test