Keywords NS2, NSG, P2P,AODV, DSDV.

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1 Volume 5, Issue 3, March 2015 ISSN: X International Journal of Advanced Research in Computer Science and Software Engineering Research Paper Available online at: Special Issue on 2 nd International Conference on Electronics & Computing Technologies-2015 Conference Held at K.C. College of Engineering & Management Studies & Research, Maharashtra, India A Trace Study and Performance Analysis of Wireless Network Using NS2 Neha M Qureshi Vidyalankar Institute Of Technology Mumbai, India Abstract This paper presents how to use simulation for designing and studying wireless networks. In order to achieve the defined task, analyze literature sources related to wireless communication networks. Briefly describe the basic wireless networks categories. Analyze the Network simulator ns-2 and give its detailed description. Present a brief comparison of ns-2 simulator with other open source network simulators. Specify the configuration for the simple wireless network with two nodes first and then with many nodes and create corresponding model by using ns-2 simulator. Demonstrate selected characteristics of the specified network configuration using the simulation model. Keywords NS2, NSG, P2P,AODV, DSDV. I. INTRODUCTION A wireless network is any type of computer network that uses wireless data connections for connecting network nodes. A wireless network enables people to communicate and access applications and information without wires. This provides freedom of movement and the ability to extend applications to different parts of a building, city, or nearly anywhere in the world. Wireless networks allow people to interact with or browse the Internet from a location that they prefer. A network is defined as the group of people or systems or organizations who tend to share their information collectively for their business purpose. A wireless local-area network (LAN) uses radio waves to connect devices such as laptops to the Internet and to your business network and its applications. When you connect a laptop to a Wi Fi hotspot at a cafe, hotel, airport lounge, or other public place, you're connecting to that business's wireless network. In the past, some believed wired networks were faster and more secure than wireless networks. But continual enhancements to wireless networking standards and technologies have eroded those speed and security differences. The reasons for using wireless network are cost effectiveness of network deployment, and its applicability to environments where wiring is not possible or it is preferable solution compared with wired networks. When designing wireless networks and/or studying their behavior under various conditions, software simulation tools are often used. Here in this paper we have used NS2 (Network Simulator 2) as the simulation tool. Fig: 1 A Network II. WIRELESS NETWORK An ad-hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any stand alone infrastructure or centralized administration. In mobile ad-hoc networks where there is no infrastructure support as is the case with wireless networks, and since a destination node might be out of range of a source node transmitting packets; a routing procedure is always needed to find a path so as to forward the packets appropriately between the source and the destination. Within a cell, a base station can reach all mobile nodes without routing via broadcast in common wireless networks. In the case of ad-hoc networks, each node must be able to forward data for other nodes. This creates additional problems along with the problems of dynamic topology which is unpredictable connectivity changes [1].Peer-to-peer (P2P) content distribution networks are powerful systems that utilize the bandwidth resources of their 2015, IJARCSSE All Rights Reserved Page 11

2 users. The performance of a P2P network is highly dependent on the users willingness to contribute their bandwidth. However, selfish (rational) users tend not to share their bandwidth without incentives[2] Peer-to-peer (P2P) networks have recently grown in popularity for a variety of applications such as content distribution, streaming multimedia, and voice-over-ip. P2P networks are often built around a decentralized architecture to distribute data in a manner that offers high availability ofcontent, inherent fault-tolerance, and efficiency. III. BACKGROUNDKNOWLEDGE AND RELATED WORK A. Ad-hoc Networks A wireless ad hoc network (WANET) is a decentralized type of wireless network. In mobile ad hoc networks, mobile devices are usually carried by humans, so the movement of such devices is based on human decisions and social behaviour. It is important to consider the behaviour of individuals moving in groups and between groups because the mobile devices are carried by individuals in the community. In order to capture this type of behavior, group mobility must be modeled. Such a model is heavily dependent on the structure of the relationships among the people carrying the devices. As a basic characteristic of such a model the following assumption is made. In social networks, clustering appears to be far greater than in networks based on random stochastic models. This is related to the fact that humans usually organize themselves into communities. The effective utilization of localized and time bound networks as means for sharing information is impacted by both, the networking protocols and the mobility and communication patterns. This means that in this localized and time bound framework the need for the network establishment dictates how ad hoc routing and P2P protocols are used. This need is dependent on the need of people to share certain information which shapes the topology of the network as well as the traffic on the application level in the network. The people who want to use the ad hoc network as a means for information sharing are part of an underlying social network that shows the way people are interconnected based on specific content or descriptors of content they require and offer. Fig.2 Ad-Hoc Network B. Defined Knowledge of ad hoc wireless network An ad-hoc or peer-to-peer wireless network consists of a number of computers each equipped with a wireless networking interface card. Each computer can communicate directly with all of the other wireless enabled computers. They can share files and printers this way, but may not be able to access wired LAN resources, unless one of the computers acts as a bridge to the wired LAN using special software. Mobile ad hoc wireless devices are typically lightweight and battery operated. An ad hoc network is made up of multiple nodes connected by links. Links are influenced by the node's resources (e.g., transmitter power, computing power and memory) and behavioural properties (e.g., reliability), as well as link properties (e.g. length-of-link and signal loss, interference and noise). Since links can be connected or disconnected at any time, a functioning network must be able to cope with this dynamic restructuring, preferably in a way that is timely, efficient, reliable, robust, and scalable. The network must allow any two nodes to communicate by relaying the information via other nodes. A path is a series of links that connects two nodes. Various routing methods use one or two paths between any two nodes; flooding methods use all or most of the available paths. Fig.3 Ad-hoc network representing nodes 2015, IJARCSSE All Rights Reserved Page 12

3 C. Peer-to-Peer wireless network Peer-to-peer file sharing is the distribution and sharing of digital media using peer-to-peer (P2P) networking technology. P2P file sharing allows users to access media files such as books, music, movies, and games using a P2P software program that searches for other connected computers on a P2P network to locate the desired content. The nodes (peers) of such networks are end-user computer systems that are interconnected via the Internet. Peer-to-Peer (P2P) is a way of structuring distributed applications such that individual nodes have symmetric roles. Rather than being divided into clients and servers each with quite distinct roles, in P2P applications, a node may act as both a client and a server. In Client/Server architecture the Client communicates only with the Server for all information needs but as the number of Clients increases performance degrades due to increase in the Server Load. Fig.4 Peer to Peer Network A peer-to-peer, or P2P, file transfer service allows the user to share computer files through the Internet. Examples of P2P services include KaZaA, Gnutella, Morpheus, and BearShare. These services are set up to allow users to search for and download files to their computers, and to enable users to make files available for others to download from their computers. D.Wireless Network Categories Many types of wireless communication systems exist, but a distinguishing attribute of a wireless network is that communication takes place between computer devices. These devices include personal digital assistants (PDAs), laptops, personal computers (PCs), servers, and printers. Wireless Networks can be categorized as follows. a. PAN - Personal Area Network b. WLAN - Wireless Local Area Network c. WAN - Wide Area Network d. MAN - Metropolitan Area Network e. DAN - Desk Area Network[3] IV. DIFFERENT PROTOCOLS USED There are many protocols available through which we can simulate our required results in wireless communication. In this section, we briefly describe the key features of the DSDV,TORA, DSR, and AODV protocols. A. Destination-Sequenced Distance Vector (DSDV) DSDV is a hop-by-hop distance vector routing protocol requiring each node to periodically broadcast routing updates. The key advantage of DSDV over traditional distance vector protocols is that it guarantees loop-freedom. B. Dynamic Source Routing (DSR) DSR uses source routing rather than hop-by-hop routing, with each packet to be routed carrying in its header the complete, ordered list of nodes through which the packet must pass. The key advantage of source routing is that intermediate nodes do not need to maintain up-to-date routing information in order to route the packets they forward, since the packets themselves already contain all the routing decisions. This fact, coupled with the on-demand nature of the protocol, eliminates the need for the periodic route advertisement and neighbor detection packets present in other protocols. C. Ad Hoc On-Demand Distance Vector (AODV) AODV is essentially a combination of both DSR and DSDV. It borrows the basic on-demand mechanism of Route Discovery and Route Maintenance from DSR, plus the use of hop-by-hop routing, sequence numbers, and periodic beacons from DSDV. V. NS2 SIMULATOR Network Simulator version 2 widely known as NS-2 is a discrete event driven network simulation tool for simulation of network to study the dynamic nature of network. It is an open source solution implemented in C++ and Otcl programming languages at UCB (University Of Carolina Berkley). NS-2 provides highly modular platform for simulation of wired as well as wireless networks. NS-2 supports different network components, protocols like TCP, UDP,FTP and traffic sources like CBR etc. Results of the simulations are provided with in a trace files that contains the entire occurred event during the simulation. The output of simulation is visualized through Nam (Network Animator). 2015, IJARCSSE All Rights Reserved Page 13

4 NS-2 size in terms of line of codes is above 200k written in C++ and TCL and 350 page manual. ns-2 is portable tool that works on most UNIX and Windows like operative systems. Ii it supported on Linux (Ubuntu, Fedora etc.), FreeBSD, SunOS/Solaris, HP/SGI, and Windows 95/98/NT/ME/2000/XP. Fig.5 Structure of NS2 A. Programming Languages in NS2 NS is an object oriented simulator, written in C++, with an OTcl interpreter as a frontend. The simulator supports a class hierarchy in C++ (also called the compiled hierarchy in this document), and a similar class hierarchy within the OTcl interpreter also called the interpreted hierarchy in this document). The two hierarchies are closely related to each other; from the user s perspective, there is a one-to-one correspondence between a class in the interpreted hierarchy and one in the compiled hierarchy. The root of this hierarchy is the class Tcl Object. Users create new simulator objects through the interpreter; these objects are instantiated within the interpreter, and are closely mirrored by a corresponding object in the compiled hierarchy. The interpreted class hierarchy is automatically established through methods defined in the class Tcl Class. user instantiated objects are mirrored through methods defined in the class Tcl Object. There are other hierarchies in the C++ code and OTcl scripts; these other hierarchies are not mirrored in the manner of Tcl Object. Fig.6 Programming Structure of NS2 Ns uses two languages because simulator has two different kinds of things it needs to do. On one hand, detailed simulations of protocols requires a systems programming language which can efficiently manipulate bytes, packet headers, and implement algorithms that run over large data sets. For these tasks run-time speed is important and turnaround time (run simulation, find bug, fix bug, recompile, re-run) is less important.ns meets both of these needs with two languages, C++ and OTcl. C++ is fast to run but slower to change, making it suitable for detailed protocol implementation. OTcl runs much slower but can be changed very quickly (and interactively), making it ideal for simulation configuration.ns (via tclcl) provides glue to make objects and variables appear on both langauges. VI. CONCLUSION AND FUTURE WORK Here in this paper we have shown the simulation results of wireless ad-hoc or p2p network. The basic simulation results shown the packet flow from souce node to destination node. It uses TCP/UDP agents for traffic flow. Here we also can able to see the flow of packets through nam window(network animator) and we can analyze the flow with the help of graph (nodes versus throughput).the drop in packets we can also able to analyze and respectively we can conclude the results. Here the future scope is that we can use other protocols instead using AODV, DSR,DSDV. In the present scenario where internet is basic need we should have larger bandwidth in order to carry out our daily work. By using Bittorrent protocol we can save bandwidth and we can overcome the Freeriding problem also. 2015, IJARCSSE All Rights Reserved Page 14

5 REFERENCES [1] Sachi Pandey, Vibhore Tyagi Performance Analysis of wired and wireless network using NS2 simulator [2] Michael Sirivianos Jong Han Park Rex Chen Xiaowei Yang, Free-riding in BitTorrent Networks with the Large View Exploit [3] Sirwan A.Mohammed Prof. Dr. Sattar B.Sadkhan Sannell Design of wireless network based on ns2 Volume 3, No. 12, December 2012 [4] Lokhande S.N.,Dr. khamitkar S.D. Design and Simulation of Wireless Ad Hoc Network Using NS2 Simulator International Journal of Engineering Research and Development,Volume 9, Issue 12 (February 2014), PP Bin Tang, Zongheng Zhou, Anand Kashyap and Tzi-cker Chiueh An integrated approach for P2P file sharing on multi-hop wireless networks. [5] Almargni Ezreik, Abdalla Gheryani, Design and Simulation of Wireless Network using NS-2 2nd International Conference on Computer Science and Information Technology (ICCSIT'2012) Singapore April 28-29, 2012 Fig.7 nam output for $ nodes Fig.8 results of 4 nodes Fig.9 nodes versus throughput 2015, IJARCSSE All Rights Reserved Page 15

6 Fig.10 dropping of packets. Fig.11 nodes versus througput 2015, IJARCSSE All Rights Reserved Page 16