# An Efficient and Reliable Algorithm for Wireless Sensor Network
## 3 Proposed Methodology
### Proposed Protocol  
The proposed model of EERASCA is shown in Figure 1 and it is implemented by using the SD message, connectivity of lists, the core election process, receiver group formation, mesh formation, data forwarding process through unicasting and multicasting, an algorithm of the proposed EERASCA and finally the implementation of the protocol.  
EERASCA is a receiver-initiated mesh-based algorithm. At the start of the communication, the first receiver that wishes to include in the receiver group will broadcast SD message to the neighbors. If any group exists, then the receiver will receive the group confirmation reply. However, if no group existed, then the receiver will announce himself as a group leader and start broadcasting a message about the group's formation. This receiver node is known as a group leader or core node, and now it forms a connectivity list. Through connectivity lists, nodes are connected and transmit and receive the data from the source node. Through SD message, all the nodes are aware of other nodes location and battery capacity within the receiver group.  
At the start of the communication process, the first node that starts the communication is selected as a core node by default. However, after the core failure, the group members shared the SD messages with all the interested receiver and the receivers that want to be the member of the group will form the receiver group. The group will contain the receivers  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Stage No.** & **Hierarchy of the Paper** & \
\begin{tabular}{c} **Previous/Base Protocol** \\ **(ERASCA)** \\ \end{tabular} &
\begin{tabular}{c} **Proposed Protocol** \\ **(EERASCA)** \\ \end{tabular} \\ \hline Stage 1 & SD Message & Similar & Similar \\ Stage 2 & Connectivity List & Similar & Similar \\ Stage 3 & Core Election Process & Similar & Similar \\ Stage 4 & Mirror Core Election Process & Similar & Similar \\ Stage 5 & Receiver Group Formation & Similar & Similar \\ Stage 6 & Mesh Formation & Similar & Similar \\ Stage 7 & Data Forwarding Process & Similar & Different \\ Stage 8 & Algorithm & Similar & Different \\ Stage 9 & Mode of Communication & Similar & Different \\ \hline \hline \end{tabular}
\end{table}
Table 1: Comparison of ERASCA and Proposed EERASCA Protocol.  
with similar interest. Now all the receivers will conduct an election for the core node, and the most suitable receiver having the maximum battery capacity and suitable location (within the center of the group) is selected as a core node. Now it is the responsibility of the core node to maintain and update the receiver group. After the receiver group formation, the mesh formation will continue, and it is explained in detail in Section 5.  
In the previous protocol, the data are forwarded within the mesh through flooding, but the data are forwarded within the mesh through unicasting and multicasting in the proposed protocol. The proposed protocol improves the reliability and efficiency in term of throughput and overhead by avoiding flooding. The proposed algorithm is implemented through NS-2. The experimental implementation of EERASCA assures the superiority over ERASCA in term of overhead, PDF and throughput.