Application and end user needs that the project relate to: 

The project is related reducing the packet flooding across the wireless sensor networks. In general due to the DoS across the wireless sensor networks, the situation of packet flooding will occur across the network. The main aim of this application is to avoid the situation of packet flooding and also mitigate the DoS attacks on the WSN. The required application is developed using OPNET Modeller simulation tool and the end users would the WSN users for this application. 

Technology that the project relate to:

Wireless Sensor Networks technology is used in this project. A WSN with 50 nodes is created using the simulation tool and the actual simulation is done on these nodes.

 Connecting or grouping of several people or computers together to exchange required data for the sake of business development can be referred as a network. The definition of a network in computer terminology is referred as a number of computer devices interlinked with one another technically to exchange information for the sake of multitasking and document printing so on. Networks can be of two types and they are wired networks and wireless networks. In wired networks nodes are connected physically with each other whereas in wireless networks nodes in a network will not have any connection between them physically. 

                                 There is a good increase in the connectivity of number of computers to a wireless network without using any wired connections. Because of this heavy processing power is created because of the packet flooding on the nodes of the wireless network by the processing power load on them. In this research project I have concentrated significantly on the packet flooding caused in the MANETs using a fresh layer known as “Sensor Medium Access Control Layer” in simple called SMAC layer. All the services needed for the implementation of packet flooding are contained in this layer. 

                             First of all, clear knowledge about MANETs is very much necessary for the project. A “Mobile Ad-hoc Network” is an independent system designed with mobile nodes. The mobile nodes that are ready to receive information are the key elements required for the construction of the MANETs. A MANET infrastructure is less approach to a wireless local area network (WLAN/WLL) etc.The nodes and router are configured to construct tis network without using any wireless connections. Hence across the packet traffic the topology is changed rapidly. The information packet delivery is done using various types of mobile ad hoc networks. 

                            Knowing about the MANET and Ad hoc networks is required initially before knowing about the packet flooding across a network. In my research it is known that MANET is a type of wireless Ad hoc network, this type of network in general routable at the link layer which is at the top. A best instance for MANET is “802.11 wi-fiwireless networks”. There are several routing methods that can be used for creating packet flooding in a network, and routing protocols also comes under these routing techniques. Therefore knowing about the routing protocols is very much necessary for this project. Routing is as technique which is utilized to identify the route across the entities between the nodes. The routing protocols are of different types and the most used routing protocols are IGRP “Interior gateway routing protocol”, RIP “Routing information protocol”, BGP “Border gateway protocol” and OSPF “open shortest path first”. 

                            Once the information of all the above protocols is known, it will be easier to work on the research issue considered in the aims and objectives that is regarding the packet flooding across the MANETs. The research regarding the packet flooding by the wireless Ad-hoc routing protocols is aimed in this dissertation. Based on the research work it is divided in terms of reactive protocols, proactive protocols and hybrid protocols. There for the concept of packet flooding can be known clearly.

 Problem or research question (motivating why this thesis work is important): 

                           I have selected is specific concept as by project work because of the key reason that is to address the issues and drawbacks observed in the wireless networks used at present and therefore the problems occurred during wireless communication can also be addressed by analyzing the significance of network that is proposed for packet flooding and the advantages that can be attained with the proposed network. With this dissertation work I have experienced a great knowledge regarding the wireless networks.  

Current (state of art) solutions used to handle the above problem or research question: 

Maintaining the wires across the complete network is really an expensive deal and even there will be more chances for the link failures if more cables are used. Therefore I have selected the wireless networks for my research. There is an availability of extending a network from a location to the other in case of the wireless networks. The key problems that are mostly observed in wireless networks are pathless and effect on the entire output that is caused because of the multipath propagation. 

                            In my research I was attracted to extended storage property of “mobile wireless sensor communication networks and preceded my research in that direction. Using the Ad-hoc networks only a single point can be accessed and for some users the network can be accessed. Even in case there is no infrastructure also the communication is done in these networks. In these networks routing protocols are interesting factors. Because of all these factors I have selected this concept as my research project. The concepts of reactive, proactive and hybrid protocols are related to my master’s syllabus where proactive protocols  are used for requesting to a neighbor across the network, reactive protocols in making the route while transferring the data and hybrid protocols adopts both the proactive and reactive protocols. These concepts are really interesting while knowing in detail about them. 

                          Considering the literature review of the project Ad-hoc grid layer methods are proposed by AksentiGranrov, Bekimcilkyu in order the grid systems to be implemented. All the services required for the implementation of grid systems are available with this grid layer.  In grid based MANETs, the service discovery is proposed by Tzung-shichen, Tsai, Hau-Wen, chih-ping chu members of IEEE. In order to use mobile ad hoc networks, this service discovery is very much necessary. As these MANETs are dynamic in nature adoption of traditional service discovery solutions is not possible. In have presented an architecture based on protocol in the MANET. The MANET is taken as 2-D logical grid, because of using this approach we can effectively reduce the expenses of registering and discovering and can implement a large network. 

Following are the research questions identified in this project 

  • What are the common problems due to packet flooding across wireless networks like Mobile ad hoc networks (MANETs)
  • How to resolve the situation of packet flooding and mitigate the DoS attacks on MANETS

 Proposed solution approach (hypothesis about solution or answer or method to find answers): 

As mentioned OPNET Modeller is used as the simulation tool in this project and it provides lot of models to simulate the wireless networks like MANETs and WSN. Two different scenarios are created in this project, where the normal scenario has the DoS attacks and the second scenario deals with mitigating DoS attacks. 

A MANET with 50 nodes is created in this project and AODV is used as the routing protocol. In general the DoS attack modifies the routing properties of the protocol and thus the key attributes of AODV are altered to create the packet flooding over the network. The actual attributes edited in this context are as given below. Email application is used in this project to create the traffic over the network and the performance of the MANET against the DoS attacks using the below parameters 

Email performance across the network against the traffic and packet sequences and following are the actual performance metrics used in this context and they are listed as below 

  • Download response time in seconds
  • Traffic received in bytes per sec
  • Traffic received in packets per sec
  • Traffic sent in bytes per sec
  • Traffic sent in packets per sec
  • Upload response time 

Apart from the Email, the wireless LAN metrics are also used and they are as listed below 

  • Data dropped due to buffer overflow
  • Data dropped due to retry threshold exceed limit
  • Delay
  • Load
  • Medium access delay
  • Network load
  • Retransmission attempts
  • Throughput 

Second scenario is created with DSR routing protocol and the performance of the network is estimated using the corresponding metrics. The situation of packet flooding is created at the routing protocol level and the overall performance of the network is estimated using the similar parameters. 

Once both the scenarios are created the simulation is run for one hour and the corresponding scenarios are compared against the performance metrics used. Based on the comparison results the best performing routing protocol against the packet flooding is estimated and the corresponding DoS attacks are mitigated.  

Experiment, analysis, verification, test or proof method to use: 

As mentioned the required experimental setup is done using OPNET modeller tool. The required scenarios to be compared are created using this simulation tool. Once the simulation is run against the performance metrics as mentioned above some graphs are generated and they are compared for both the scenarios. Based on the comparison results the required evaluation is done. 

Technical tools or measurement equipment etc. needed to do the work: 

As mentioned in the previous section there are two scenarios used across this simulation process and to derive the corresponding scenarios OPNET modeller is used as the simulation tool. OPNET modeller has many advantages when compared to the other simulation tools like NS2 and OMINET in terms of level of models supported and also the user interface provided to create a wide range of networks. NS2 is also much popular as OPNET modeller, but the only disadvantage with NS2 is that, it is complex in nature and involves lot of coding, where these aspects completely eliminated in OPNET modeller. OPNET also provides many model families against the wireless communication and the main importance of this tool lies with the aspect like a simple drag and drop operations can improve the simulation procedure and the object palette available with OPNET provides many objects to be configured.

All the required objects can be dragged from this palette and they are configured as per the scenario requirements to create the actual network setup.  The simulation model involves, creating the required network, verifying the model consistency, running the simulation and finally evaluating the results. These steps are followed in creating any type of network and thus OPNET can be considered as the simple solution to create both the wired and wireless networks. Apart from these models, OPNET also provides the latest technologies like MANETs, wireless mesh networks and Zigbee networks also and thus all these models can be created and the performance of the networks can be evaluated easily.