Results and Analysis
Introduction
Main objective of this MS Project Dissertation is to evaluate the results obtained after running the three scenarios for one hour. As discussed in the previous chapter three scenarios are used in this simulation, where AODV is used as the routing protocol for first scenario, DSR is used as the routing protocol for second scenario and OLSR is used as the routing protocol for third scenario. Packet flow and the corresponding traffic analysis against the packet losses for the three scenarios is presented in this chapter and also the performance metrics used in the simulation process are given in the form of graphs and the resultant graphs are compared to understand the performance of the individual routing protocols and the corresponding resultant graphs are as given below
Results of Email application performance
It is discussed that Email application is used in this simulation and with this application the required traffic is generated. Various performance metrics of Email are used across the simulation process and all the performance metrics related to packet analysis and also the traffic analysis are considered for the performance evaluation and all these metrics are considered for three scenarios. Each and every scenario is considered and they are compared against the Email performance metrics and they are as given below
Email Download response time in seconds
Download response time indicates the number of packets per second used in downloading the email from the email server and in this context a single wireless LAN server is used as the email server and this time indicates the time taken to download the email from the wireless LAN server. In general the download response time indicates the performance of the individual routing protocols considered and it should be less enough to indicate a less packet loss across the network and if it is more then it indicates that the corresponding packet loss is more and it should be optimized against the routing protocol performance. The actual comparison graph of the three routing protocols considered in terms of the email download response time is as given below
Email download response time incurred for the three routing protocols is shown in the above graph. When the email download response time is considered it is observed that the overall download response time is more with the AODV is used as the routing protocol when compared to the other scenarios. It is observed that the minimum email download response time is incurred with the OLSR routing protocol and it was initially high and later it was reduced and a minimum download response time is incurred. When the download response time is less it indicates that there is no packet losses across the network and due to the less packet loss the email contents are downloaded at a speeder rate and when the case with DSR is considered the download response time in this case is also less when compared to AODV and more than the OLSR routing protocol. From the overall analysis it is clear that when there is more packet loss across the network the overall download response time has increased a lot and in this context OLSR is the best routing protocol to prevent the packet losses on the network and AODV has shown more packet loss on the network.
Traffic received in bytes per second
Traffic received has the major importance in analyzing the packet loss across the network and in this context the overall traffic received on the network in bytes per second is analyzed against the three routing protocols. AODV, DSR and OLSR routing protocols are analyzed in this context and they are compared in terms of traffic received in bytes per second and the corresponding results are given as below
From the above graph it is observed that maximum traffic is received with the OLSR routing protocol and the minimum traffic is received with the AODV routing protocol. When the traffic received in bytes per second is considered it is clear that when the traffic received in bytes per second is more the overall packet loss is more due to the fact that when the traffic is more the scope to lose the traffic in terms of packets is more. In this context the traffic received is more with the OLSR routing protocol as it has the tendency to lose more packets when compared to the other ad hoc routing protocols and even the value is not constant throughout the simulation time. AODV has a constant traffic received across the network when compared to the other two routing protocols and thus the overall packet loss is less as the traffic received is less and due to this the congestions will be less and thus the packet loss will be less when compared to other routing protocols. When the case with the DSR routing protocol is considered the overall traffic received is more and also the corresponding packet loss is also more and even the traffic received is not constant and this indicates that the packet loss is more due to the expected congestion levels on the network. From the overall analysis it is clear that AODV can be considered as the best performing routing protocol in terms of traffic received and minimum packet loss across the wireless LAN server.
Traffic received in packets per second
Traffic received in packets per second will give the exact analysis of the network in terms of packet losses and in this context the three routing protocols are evaluated. In general when the traffic received is more across the network the overall packet loss will also be more due to the reason that the overall congestion levels will be increased on the network and also the nodes and the server will be busy in processing the traffic and this leads to packet flooding. When the three scenarios are compared the corresponding packet loss situation is given in the below comparison graph
Overall traffic received in packet per second is given in the above graph for the three routing protocols. It is observed that the traffic received in packets per second is more with the OLSR routing protocol and it has received more number of packets in the form of traffic flooding and due to this the chances of losing the packets are increased a lot. When the case with AODV routing protocol is considered it has shown a minimal value and thus the traffic received in packets per second has reduced a lot. Due to this process the overall congestion is decreased and also the chances for packet flooding are reduced and the overall packet loss will be less when compared to the other scenarios. DSR has shown an optimal performance in terms of packet loosing and the losing ration is more when compared to AODV and less when compared to OLSR thus this indicates that AODV can be considered as the best routing protocol to minimize the packet looses in the network. When the traffic received in packets per second has reduced across the network the chances for packet flooding are minimized and in this context AODV has reduced the packet flooding chances and the nodes along with the wireless LAN server now can lose a minimum level of packets on the network.
Traffic sent in bytes per second
When the traffic sent is more, the levels of congestion on the network will be more and due to these levels the chances of losing the packets are increased. The three routing protocols considered are analyzed in terms of traffic sent in byte per second and the resultant comparison graph is given as below. When the traffic sent is constant across the network and when it is less it indicates that packet loss is less on the network due to the corresponding routing protocol and the corresponding graph is as given below
Above graph shows the comparison of the traffic sent in bytes per second for the three routing protocols. When the traffic sent in bytes per second is compared it is clear that the overall traffic sent is more with the OLSR routing protocol and even this value is not constant across the network. AODV routing protocol has shown an optimal performance levels in terms of the traffic sent in bytes per second this value is constant throughout the simulation time and this indicates that the chances of losing the packets at the node and wireless LAN server are reduced and thus the overall performance of the network in terms of packet loss is optimized on the network. When the case with the DSR routing protocol is considered the packet loss is more on the network due to the fact the dynamic routing forming sequences are more on the network and in the process of updating the routes dynamically the packets are lost and thus from the overall analysis it is clear that the overall performance of the network has increased in terms of the packet loss due to the implementation of the AODV routing protocol. Thus even in this case the performance of the network is on the top standards at the AODV routing protocol levels.
Traffic sent in packets per second
Traffic sent in packet per second given an idea in analyzing the packet drop on the network and in general if the packet drops on the network is more it is due to the fact the traffic sent is more in packets per second. If more traffic is sent from the nodes of the network, the overall packets transmitted to the server will more and this increases the chances to lose the packets on the network and the actual analysis of the packet loss due to the traffic sent by the three scenarios is given in the below graph
The average traffic sent in packets per second is shown in the above comparison graph. It is observed the overall traffic sent is more with the OLSR routing protocol as the OLSR has more tendency to make the mobile nodes on the network to send more traffic at a constant rate to the server and due to this all the nodes will sent continuous requests to the server. With this the server will become busy in processing the requests of the nodes and the chances of losing the packets will be more with the OLSR routing protocol. When the case with AODV is considered it is clear that a low rate of traffic is sent and also the AODV will make the nodes to sent the routing requests to the neighboring nodes at a constant rate and this will reduce the burden on the server and thus the server can process the requests from the nodes at a constant rate and thus the overall congestion on the network is reduced a lot. When the case with the DSR is considered the overall traffic sent is more when compared to AODV and this is due to the reason that the dynamic nature of the nodes will make the server to process all the requests at a time and the tendency to lose the packets has increased. So from the overall analysis it is clear that that AODV has shown an optimal performance in terms of packet looses against the traffic sent in packets per second.
Email upload response time in seconds
Upload response time has the crucial role to play in analyzing the packet loss on the network and in general if the upload response time is more this indicates that the packet loss is more on the network due to the routing protocol. When the three scenarios are considered in this context the to understand the overall upload response time the resultant comparison graph is as shown below
The actual email upload response time to upload the email contents incurred by the three routing protocols is shown in the above graph. It is clear that the upload response time is more with the AODV routing protocol and this is due to the fact that the static nature of the routing protocol will consume more time to upload the content and in this process the chances to lose the packets are increased when compared to the other routing protocols like OLSR and DSR. When the case with the OLSR routing protocol is considered it has shown a minimum download response time and thus it indicates that the overall packet loss in terms of upload response time is very less when compared to the AODV and DSR routing protocol and DSR has shown an optimal performance with respect to the upload response time. Thus from the overall analysis it is clear that when the packet loss is more on the network the upload response time has increased and in this context OLSR is proved to the best routing protocol to minimize the packet loss on the network in terms of upload response time. Thus when the Email performance metrics are considered apart from the download response time and upload response time the overall performance of the AODV is considered to be at the maximum level in terms of packet loss and with the implementation of the AODV routing protocol on the network the overall performance of the network has increased a lot.
Performance metrics of wireless LAN server
Performance of the wireless LAN is also considered to understand the packet losses due to the server aspects and few metrics are considered in this context. All the three routing protocols are analyzed against these metrics and based on the simulation run the results are analyzed in this section and the comparison graphs are given as below
Data dropped due to buffer overflow
Buffer overflow is one of the important reasons to lose the packets as the data will be dropped and due to this the performance of the network will be degraded. When the three scenarios are compared against the data dropped due to the buffer overflow the resultant graph is as shown below. In general if the data dropped is more then it indicates that the packet loss is more on the network and the actual performance of the AODV, DSR and OLSR is given in the below graph
The average data dropped across the wireless LAN due to the buffer overflow is as shown in the above screen. It is observed that the overall data drop is more with the DSR routing protocol when compared to the other routing protocols and due to the dynamic nature of the nodes and the server they will improve the tendency to lose the packets and thus the overall packet loss will more with the DSR routing protocol. When the case with the OLSR is considered it is observed that it has shown an optimal performance and the data dropped is less when compared to the DSR routing protocol and AODV has shown an optimal performance in terms of the data dropped. When the data drop on the network is less then automatically the packet loss would be low and this indicates that the AODV is the best routing protocol to reduce the packet loss on the network and the overall performance of the network can be improved a lot. DSR has shown maximum data drop on the network and also the packet loss is more and thus few refinements should be done in this context to improve the performance of the network. It is also observed that all the routing protocols has shown a constant data drop across the network and this is due to the random mobility model chosen and AODV is the best across this simulation to optimize the packet losses.
Wireless LAN delay in seconds
Wireless LAN delay is considered to be the important metrics in analyzing the performance of the overall network in terms of packet loss. In general if the delay is more on the network then it indicates that the performance of the network degraded due to the more packet loss and in this context the three scenarios are considered and analyzed and the resultant comparison graph is as shown below
Wireless LAN delay across the network due to three routing protocols is shown in the above graph. From the resultant graph of the wireless LAN delay it is observed that the overall delay on the wireless LAN server is more due to the DSR routing protocol and if the delay is more on the network it indicates that the server has loose the packets at a constant rate and due to this the corresponding delay is incurred on the network. A minimum delay is observed with the OLSR routing protocol and even AODV has shown an optimal performance in terms of delay on then network. OLSR is proved to be the best routing protocol in this context and has imposed a very less delay on the network and due to this packet loss is also reduced a lot on the network and when the case with the AODV is considered the overall packet loss is at constant rate and at the end of the simulation it is reduced to zero and this indicates that even AODV is better to be considered when packet loss reduction is considered. Thus from the overall analysis it is clear that AODV and OLSR are proved to be the best routing protocols to be considered to reduce the delay and also the packet loss on the wireless LAN server.
Load on the wireless LAN server
In general the load on the wireless LAN server will indicate the overall packet loss on the network and if the load on the network is more then automatically the packet loss will more as the load on the network will lose the communication and data packets across the network. Three routing protocols like AODV, DSR and OLSR are considered for comparison for analyzing the load on the network and the resultant comparison graph is as shown below
When the load on the network is considered it is observed that the overall load on the network is more due to the OLSR routing protocol and due to the heavy load on the network the tendency to lose the packets is increased and thus in terms of load OLSR has shown a poor performance and thus it should be optimized. When the case with AODV is considered initially the load on the network is more and then it is reduced a lot due to the routing performance of the protocol and DSR has shown a minimum load on the network when compared to other routing protocols. This indicates that when the load on the wireless LAN server is considered the optimal packet loss is observed with the DSR routing protocol due to its dynamic nature and thus in this context DSR can be considered as the best routing protocol to reduce the load and also packet loss on the network and even the performance of AODV is also better in terms of reducing the network load and the corresponding packet loss on the network. When all the three routing protocols are considered AODV can be considered as the best one as a constant load on the network is incurred due to this routing protocol.
Wireless LAN medium access delay in seconds
Wireless LAN medium access delay is the actual delay occurred across the medium of communication and as wireless is the medium used for this communication this delay plays an important role in estimating the overall impact on the packet loss situations. For this purpose the three routing protocols considered are analyzed and compared in terms of their role in providing the medium access delay and the corresponding comparison graph is as shown below
The average medium access delay on the wireless LAN server due to the three routing protocol is shown in the above screen. When the medium access delay is considered it is clear that the overall delay is more with the DSR routing protocol and this delay is more due to the impact of the dynamic nodes on the network. In general when the nodes feel a particular route across the network to reach the destination Email server is not working then automatically they will make the medium busy to built a new route to reach the destination and due to this the medium will lose the important packets on the network and thus the packet loss is more with the DSR routing protocol. When the OLSR routing protocol is considered it is observed that there is a very minimum medium access delay on the network and due to this the packet loss is also reduced a lot and even the value is constant across the communication process. AODV has shown an optimal performance and due to this the packet losses are reduced a lot when compared to the DSR routing protocol and thus from the overall analysis it is clear that the performance of the network can be optimized against the packet looses with the implementation of OLSR and AODV routing protocols.
Wireless LAN network load
Wireless LAN network load can be considered as the important performance metrics to estimate the overall performance of the network in terms of load and also the related packet loss due to this network load. In general if the network load on the network is more it indicates that the packet loss is also more and in this context the performance of the three routing protocols is considered and the resultant comparison graph is as shown below
The average wireless LAN network load imposed due to the three routing protocols is shown in the above screen. When the network load is considered it is clear that the load on the network is more when the nodes and the server are using the OLSR routing protocol and a minimum load is imposed by the DSR routing protocol. As the nodes and the server using the DSR routing protocol will behave in a dynamic in nature the network load is reduced a lot and thus even the packet loss is also reduced a lot with this routing protocol. When the case with the AODV routing protocol is considered even this routing protocol has shown an optimal performance in this context of network load and due to this minimum network load the packet loosing conditions are reduced and also the overall performance of the network is optimized again. A constant network load is imposed due to the AODV routing protocol and again in this context AODV is proved to be the best performing routing protocol to reduce the network load and also optimize the packet loosing conditions where the packet loss is reduce a lot with both the AODV and DSR routing protocol.
Retransmission attempts in packets
The number of retransmission attempts on the network will indicates the packet loss directly as if the packets are lost across the routing process then automatically the nodes will make the retransmission attempts to reach the Email destination server. All the three routing protocols considered are compared in this context and the resultant comparison graph is as shown below
The overall performance of the routing protocols in terms of the retransmission attempts is shown in the above graph. When the number of retransmission attempts is considered it is observed that a maximum retransmission attempts is shown with the DSR routing protocol and this is due to the fact that when the nodes are dynamic in nature due to the DSR routing protocol they develop the required tendency to lose the packets and thus they keep on sending the retransmission attempts to the network. When the case with the OLSR routing protocol is considered a minimum number of retransmission attempts is made and this indicates that the OLSR routing protocol is the best routing protocol to be considered to eliminate the retransmission attempts and also to reduce the packet loss on the network. AODV has shown an optimal performance in this context and also has reduced the tendency to lose the packets at the wireless LAN server side and thus the performance of the network has improved a lot due to this routing protocol. Thus when the overall performance of the routing protocol is analyzed in the context of retransmission attempts and packet losses OLSR and AODV has shown an optimal performance all the time and this indicates that when the routing protocols are static in nature the overall packet loss on the network is reduced a lot.
Throughput
Throughput has a significant role to play in estimating the performance of the network in terms of the throughput and in general if the throughput is more then it indicates that the packet loss on the network is reduced a lot and in this process the three routing protocols considered are compared and the resultant comparison graph is as shown below
The average throughput occurred with the three routing protocols is shown in the above comparison graph. From the throughput analysis it is clear that a maximum throughput is incurred with the OLSR routing protocol when compared with the AODV and DSR routing protocols. Even the throughput is constant throughout the simulation time and this indicates that the packet loss is very less at the wireless LAN server side due to the OLSR routing protocol and when the case with AODV is considered it has shown a better throughput when compared with the DSR routing protocols and also there are some variations in the curve and this indicates that the overall packet loss is optimized at the end of the simulation due to the implementation of AODV routing protocol. When the case with DSR routing protocol is considered it is clear that the throughput is very less and this indicates that the overall packet loss is very high due the DSR routing protocol. Thus when all the performance metrics of the wireless LAN are considered it is clear that OLSR routing protocol can be considered as the best routing protocol to optimize and reduce the packet losses on the network and the next place is occupied by the AODV routing protocol. When the overall Email and Wireless LAN metrics are considered the average packet loss is reduce with the implementation of AODV routing protocol.
Summary of results
As the main aim of this simulation is to estimate the packet loss situations on the wireless, three scenarios are considered like AODV, OLSR and DSR and their performance against the packet losses are analyzed. Email application is used to generate the traffic on the network and from the analysis of the traffic patterns the corresponding packets are also analyzed. Few email metrics like download response time, upload response time, traffic sent and traffic received are analyzed against the packet loss from the overall analysis of the results it is clear the OLSR has shown an optimal performance in terms of packet loss at the upload and download response time. When the packets loss is estimated against the traffic sent and traffic received are analyzed the packet loss is very less with the AODV routing protocol and thus it indicates that the overall performance of AODV is more to reduce the packet loss against the email application. When the wireless LAN server metrics are considered the performance of both AODV and OLSR at the optimal levels in every aspect considered and also the OLSR has shown an optimal performance in terms of delay, medium access delay, load, network load, throughput and retransmission attempts and the AODV has shown the required performance to reduce the packet loss at the wireless LAN server side.