# Fuzzy Logic-Based Geographic Routing Protocol for Dynamic Wireless Sensor Networks
## 3 FLGR Protocol
### Message Format and Local Storage Structure  
The Hello message is the basis of the FLGR protocol. Based on Hello messages, the neighbor nodes can be found, and their location information can be obtained. The format of the Hello message is presented in Table 2.  
As given in Table 2, each Hello message has a unique sequence number, Num_seq, which can be used to indicate the freshness of the information carried by the Hello message. The ID of the Hello message denotes the unique identity label of the sending node. The neighbor node IDs and locations are also included in the Hello message, which can be used to obtain the parameter of CN. The node location can be represented by 16 Bytes. The x and y axis can be represented by 64 bits, respectively, with 1 bit to the sign of the number, 16 bits to the exponent, and 47 bits to the fractional part. Through the periodic broadcasting of the Hello message, the information table of neighbor nodes can be established. To update the neighbor node table in a timely manner, the periodicity of the Hello message changes according to the node's maximum speed. In Section 4.2, the periodicity of the Hello message is given in different scenarios. When the Hello message reaches a node, the neighbor node table will be updated. The neighbor node will be deleted in neighbor node table when its information is not included during two Hello message intervals. Once the information of a new node occurs in the Hello message, it will be added to the neighbor node table. \begin{table}
\begin{tabular}{c l} \hline \hline
**Acronyms and** & **Meanings** \\ \hline EN & Election node \\ CNR & Candidate node region \\ CN & Candidate node \\ \(n_{i}\) & Node \(i\) \\ \(l_{i}\) & Location information of \(n_{i}\) \\ \(N\) & Number of nodes in network \\ \(S\) & Area of network region \\ \(v_{\max}\) & Maximum speed of node \\ \(R\) & Transmission radius of node \\ \(t_{ij}\) & Time interval from the previous update time of \(n_{j}\) to the current moment \\  & according to the local network location table of \(n_{i}\) \\ \(r_{ij}\) & Fuzzy location region radius of destination node \(n_{j}\) according to \(t_{ij}\) \\ \(\theta_{ij}^{adv}\) & Angle of the fuzzy location region according to \(r_{ij}\) \\ \(D_{ij}\) & Distance between \(n_{i}\) and \(n_{j}\) \\ \(\rho_{kj}\) & Density of nodes in the CN of CN \(n_{k}\) (destination node \(n_{j}\)) \\ \(\rho_{global}\) & Density of nodes in network \\ \(\eta_{ij}\) & Relative density between \(\rho_{kj}\) and \(\rho_{global}\) \\ \(\Omega_{kj}\) & Distribution degree of nodes in the CNR of CN \(n_{k}\) (destination node \(n_{j}\)) \\ \(\mathbf{L}^{opt,kj}\) & Optimal locations of nodes in the CNR of CN \(n_{k}\) (destination node \(n_{j}\)) \\ \(\mu(x)\) & Gaussian subordinating degree function \\ \(E\) & Comprehensive assessment of CN \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Detailed list of acronyms and notations. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Values** \\ \hline Num\_seq & 2 Bytes \\ Hello message ID & 2 Bytes \\ Node location & 16 Bytes \\ Neighbor nodes IDs & 2 Bytes * num\_neighbor \\ Neighbor nodes locations & 16 Bytes * num\_neighbor \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Format of Hello message. In addition, other than the transmission data, the data message also contains information on the destination node and all previous forwarding nodes. The format of the data message is given as follows:  
As given in Table 3, Num_seq indicates the freshness of the information carried by the data message. Node IDs_pre denotes the IDs of all previous forwarding nodes. Nodes locations_pre denotes the locations of all previous forwarding nodes. Num_pre denotes the number of all previous forwarding nodes. In practical application, the maximum value of Num_pre should be set. This changes according to different scenarios. If the reserve space is full, the latter forwarding node information is discarded.