# Hybrid Zoning Algorithm to Optimize Overhead in Smart Mobile Communication
## 6 Results
Figure 14 shows the number of receptions of TC messages by all nodes in the network. The difference in terms of retransmissions between OLSR and Z-MPR as well as GFR and Z-GFR are reflected on the reception of TC messages. The two reductions represent a huge gain to reduce the protocol overhead and to enhance the performance of the network. Figures 15 and 16 show, respectively, the sum of packets transmitted and received at the MAC layers of nodes. The packets shown here concern the UDP sockets and the protocol overhead. We notice that GFR and Z-GFR perform better than Z-MPR. They reduce a considerable number of useless transmissions between the two zones. Z-MPR impacts the packets positively and performs better than OLSR due to the reduction of collision. This is explain by the fact that nodes do not have to resend the dropped packets, which increases the successful receptions. We reduced the number of messages by approximately 30%. However, the number of transmitted packets did not have the same reduction, because the TC messages increase. Adding the coordinates of the originator to the header of OLSR increases the size of the messages. However, the size of cancelled transmissions exceeds the size of all the extensions of the messages. Despite this increase, we reduced the number of packets exchanged in the network compared to the other protocols. Nodes in mobile communications share the same radio channel. Reducing the protocol overhead may free the channel and decrease the loss of packets. Figure 17 shows the dropped packets at the physical layers of nodes. We notice that the three modified protocols drop fewer packets than the original OLSR. Z-GFR uses a reduced number of packets at the MAC layer, which allows our protocol to free the channel and avoid collisions more than the GFR. As a result, nodes remove few packets compared to other protocols. Z-MPR removes fewer packets than OLSR because it decreases the collision at the level of MPR nodes. This helps broadcast messages to be exchanged fluently. However, decreasing the useless TC messages in GFR decreases the packets needed to transfer them, which allows the GFR to drop fewer packets than Z-MPR. Reducing the number of exchanged packets in the radio channel impacts obviously the exchange of data packets. Figures 18 and 19 show respectively the loss of packets and PDR of the UDP sockets. We remark that Z-GFR drops less data packets than the other protocols because it frees the channel. The reduced overhead permits to applications to transfer more data than the OLSR protocol. The GFR reduces considerable useless transmissions, offers fluent network and outperforms the Z-MPR in terms of PDR and lost packets. One of the consequences of the increase of the PDR and the reduction of lost packets is the increase of data transfer rate. Figure 20 shows the sum of throughput of the ten udp sockets. It proves that our solution Z-GFR exchanges packets at high rate because the protocol overhead has decreased to the maximum. Z-GFR offers 14%, 11% and 8% of bandwidth better than OLSR, Z-MPR and GFR, respectively. This helps nodes to exchange more data than the other protocols. Figure 21 shows the end-to-end delay that the data spent between source and destination. The more reliable is the network, the better is the delay. Our solution Z-GFR reduces the number of TC messages and lost packets, therefore it decreases the latency and makes the network more reliable. It performs better than the other protocols, which makes it suitable for real time applications such as voice over ip and video streaming. Figure 16: Total number of packets received at the MAC layers of nodes. Figure 17: Total dropped packets at the physical layers of nodes. Figure 19: pdr of the udp sockets. Figure 20: Throughput of the udp sockets. Figure 18: Loss of packets of the udp sockets.