Tham khảo tài liệu 'wireless mesh networks 2010 part 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Secure Routing in Wireless Mesh Networks 269 AODV protocol. The finite state machine shown in Fig. 16 depicts various states through which a neighbor node undergoes for each LMU Wang et al. 2008 . The corresponding states for the numbers mentioned in can be found in Table 2. State Interpretation 1 init 2 unexp RREP 3 rcvd RREQ 4 fwd RREQ 5 timeout RREQ 6 rcvd RREP 7 LMU complete 8 timeout RREP Initial phase no RREQ is observed Receipt of a RREP without RREQ observed Receipt of a RREQ observed Broadcast of a RREQ observed Timeout after receipt of RREQ Receipt of a RREP observed Forwarding of a valid a RREP observed Timeout after receipt of a RREP Table 2. The states of the finite state machine for a local message unit LMU To distinguish the finals states these states are shaded. Every message transmission by a node causes a state transition in each of its neighbor s finite state machine. The finite state machine in one neighbor node gives only a local view of the activities of the node being monitored. It does not in any way represent the actual behavior of the monitored node. The collaborative participation of each neighbor node makes it possible to get an accurate global picture regarding the monitored node s behavior. A node whose activity is being monitored by its neighbors is referred to as a monitored node and its neighbors are referred to as a monitor node. Each node plays the dual role of a monitor node and a monitored node for each of its neighbors. Each monitor node in the network observes a series of interleaved LMUs for a routing session. Each LMU can be identified by the source-destination pair contained in an RREQ message. Let us denote the kth LMU observed by a monitor node as sk dk . The pair sk dk does not uniquely identify an LMU because source can issue multiple RREQs for the same destination. However since the subsequent RREQs have some delays associated with them we can safely assume that there is only one active LMU sk dk in the network
