Mobile Devices Routing Using Wi-Fi Direct Technology

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Mobile Devices Routing Using Wi-Fi Direct Technology AICT 2015 : The Eleventh Advanced International Conference on Telecommunications Mobile Devices Routing Using Wi-Fi Direct Technology Ricardo Pagoto Marinho, Urbano Botrel Menegato, Ricardo Augusto Rabelo de Oliveira Laboratório Imobilis Universidade Federal de Ouro Preto Ouro Preto, MG - Brazil Email: {ricardopmarinho,urbanobm,rrabelo}@gmail.com Abstract—Information exchange between mobile devices grows This information can be shared between devices. Based on An- every day. The communication relies on a network with an droid implementation and through experiments, we observed access point (Wi-Fi, cellular, etc.) using ad hoc communication that there is a 24-character limit for the service name being because Wi-Fi Direct would avoid this dependence. Currently, Wi- published. We think that 24 characters in many cases are not Fi Direct does not support multi-hop communication or moving sufficient to give a relevant name to a service. Very often, 24 devices. This work focuses on expanding the use of Wi-Fi Direct characters are not sufficient so that all information on a route technology, so that information sent from a device can walk on the network (multi-hop). We measured the number of exchanged message can be sent. Thus, for routing algorithm experiments messages by devices using four routing protocols: i) flooding, ii) in some cases, information must be split into more than one Ad hoc On-demand Distance Vector (AODV), iii) AODV-Backup publishing. Route (AODV-BR), and iv) Location-Aided Routing (LAR). We In this paper, we intend to expand this technology’s use on see that even with some challenges one can route mobile devices the Android. By doing so, the mobile devices that use Android over Wi-Fi Direct. can communicate in a multi-hop and mobile network way (with Keywords–Wi-Fi Direct; Ad-hoc Network; Routing. devices joining and leaving). To do so, we used four ad hoc routing protocols: i) flooding, ii) AODV [5], iii) AODV-BR [6], I. INTRODUCTION and iv) LAR [7]. The flooding protocol is the simplest. With it, Mobile devices have a highlighted place in society life. the devices only send messages to its neighbors, with any type Many people have some type of mobile device. Therefore, of control. These messages allow neighbors to know that the communication using mobile devices is very typical. Apps that devices are on the network. Neighbors, on their turn, replicate help them communicate are frequently used and are popular. with any type of control the information so that every device on However, these apps rely on some sort of network so that the the network is aware of other devices. On AODV, AODV-BR messages can be exchanged, whether it is Wi-Fi or cellular. and LAR algorithms, devices that want to communicate must These types of networks are already well known and can initiate a routing discovery stage before sending any message. guarantee that information is delivered even though it may not On this stage, the device that wants to communicate starts a be possible to use them. Free and good Wi-Fi networks are not route request with its neighbors. They replicate the message easy to find or are not available [1]. In addition, the device must until it arrives on the destination device. The destination then be on the reaching area of a Wi-Fi modem so it can connect creates the reply message. This message has the route that itself to the network. Cellular networks can be found anywhere the request message went through to arrive at the destination. in a city in which they are available, even though access to When the reply message arrives on the source device, the route these networks is made by means of payment whether right is created. LAR is different from AODV because LAR uses the on time or before access. location and moving information of the destination device to Ad hoc networks can be a cheaper alternative for the forward requests. AODV-BR is a modification of AODV. The devices to communicate. In this type of network, the devices devices maintain a record of the reply messages from other communicate directly with no dependence on the access point devices so they can produce backup routes for link failure as modems on Wi-Fi networks or antennae on cellular net- cases. works. In this context, Wi-Fi Alliance has developed Wi-Fi Direct technology [2]. This technology uses a Wi-Fi interface The experiments were made to measure the number of for them to communicate in an ad hoc fashion [3]. exchanged messages by every protocol using Wi-Fi Direct. This is a new technology and few devices have it. Android During the experiments, the devices were always in the range devices have this technology. Because Android 4.0 devices are of each other. Experiments were performed by varying the equipped with Wi-Fi Direct technology, we can exploit the number of devices from two to seven. They were performed technology to communicate between devices. Currently, the to determine if the technology can scale and understand its communication only happens between two devices that are behavior as we added more devices on the network. within the reaching area of both with no hops on commu- The contribution of this paper is to show that, even with nication. Moreover, the devices must be motionless so that technology limitations, we can do ad hoc routing of Android communication can be performed efficiently. devices using Wi-Fi Direct. Botrel Menegato et al. [4] use Android’s service API to This paper is organized as follows: in Section II, we publish information such as speed, location and battery power. show several works in literature that also perform experiments Copyright (c) IARIA, 2015. ISBN: 978-1-61208-411-4 83 AICT 2015 : The Eleventh Advanced International Conference on Telecommunications on ad hoc network protocols to understand the behavior of propose a scenario where the communication is all Peer-to- the technologies and scenarios used. Section III shows how Peer (P2P), while nearly every work presented relies on a the protocols are proposed in the literature. In Section IV, certain type of group communication. we explain how we implemented the proposed protocols on the technology. Section V explains the configurations of the III. ALGORITHMS experiments. Section VI shows the results we obtained from In this section, we show how the four selected protocols the experiments on the technology and Section VII concludes are proposed. The protocols to test the technology are flooding, the work. Ad hoc On-demand Distance Vector (AODV), AODV Backup Route (AODV-BR) and Location Aided Routing (LAR). II. RELATED WORK Barolli et al. [8] propose experiments on Mobile Ad hoc These protocols were selected because they are basic Networks (MANET) using the Optimized Link State Routing protocols for ad hoc network routing. Flooding is the simplest (OLSR) protocol. Using eight different scenarios for the exper- one, AODV only uses the basic route discover approach, and iments, they collect information regarding throughput, Round- LAR is slightly more complex because it has positioning and trip Time (RTT) and package loss. To do so, they spent 150 movement information. AODV-BR was implemented to test seconds on each experiment in a closed environment with all our hypotheses to determine whether a modification on the devices reaching everyone. The experiments were performed protocols can make the technology work better. As discussed using OLSR over data flow from TCP and UDP to count the in Section II, most works used the OLSR protocol, and we did metrics. not implement it because these four protocols are sufficient to support our claims. Sharma et al. [9] use Content Centric Networks (CCN) for communication devices on a MANET to increase the message A. Flooding delivery efficiency on this network. The CCN paradigm only takes into account what the information brings from where For the flooding protocol, the nodes that participate in the it comes. Similar to Barolli et al. [8], they also use OLSR network only reply to messages sent by its neighbors without to perform the experiments. The proposed algorithm relies on any control on them. Thus, two non-neighbor nodes that have a Multipoint Relay (MPR). The work uses probabilities for a a common neighbor can identify themselves as belonging to node that is selected based on whether it is an MPR. The exper- the network. iments were performed on Android devices forming different However, with this algorithm, we have the guarantee that network topologies. Information regarding the package loss the message will go through the best path between two nodes rate, delivery time, network traffic and overhead was collected. because every node on the network will receive it. Ikeda et al. [10] propose experiments to evaluate through- put and package loss rate on MANETs using OLSR and B. AODV B.A.T.M.A.N. protocols. The devices were used on two sce- The AODV protocol is a reactive protocol. On this type of narios. One scenario has every device stationary, and other protocol, a node will know if there is a route to a destination scenario has one of the devices moving. Moreover, the devices after a route discovery phase. were on different floors of the building. This phase begins when a node s wishes to communicate Won-Suk Kim and Sang-Hwa Chung [11] proposed a mod- with another node d on the network. If node s does not have ification on AODV. They used multi-interface multi-channel a route to d, the route discovery phase starts. First, node s (MIMC) wireless mesh network issues (WMN) and adapted sends its neighbors a Route Request (RREQ) message through the protocol for these situations.
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