Vedat Coskun
Işık University
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Featured researches published by Vedat Coskun.
Wireless Personal Communications | 2013
Vedat Coskun; Busra Ozdenizci; Kerem Ok
Near Field Communication (NFC) as a promising short range wireless communication technology facilitates mobile phone usage of billions of people throughout the world that offers diverse services ranging from payment and loyalty applications to access keys for offices and houses. Eventually NFC technology integrates all such services into one single mobile phone. NFC technology has emerged lately, and consequently not much academic source is available yet. On the contrary, due to its promising business case options, there will be an increasing amount of work to be studied in the very close future. This paper presents the concept of NFC technology in a holistic approach with different perspectives, including communication essentials with standards, ecosystem and business issues, applications, and security issues. Open research areas and further recommended studies in terms of academic and business point of view are also explored and discussed at the end of each major subject’s subsection. This comprehensive survey will be a valuable guide for researchers and academicians as well as for business world interested in NFC technology.
international conference on intelligent computing | 2011
Busra Ozdenizci; Kerem Ok; Vedat Coskun; Mehmet N. Aydin
Existing indoor navigation systems face with many different technical and usability problems. In this paper we present a Near Field Communication (NFC) based indoor navigation system called NFC Internal in order to eliminate the current indoor navigation problems. NFC Internal enables an easy data transfer for indoor navigation systems just by touching tags spread over a building or a complex. The proposed system has several benefits and has potential to increase the usability of these systems. We discuss the system requirements and explain the phases of NFC Internal through use cases.
Sensors | 2015
Vedat Coskun; Busra Ozdenizci; Kerem Ok
Near Field Communication (NFC) is an emerging short-range wireless communication technology that offers great and varied promise in services such as payment, ticketing, gaming, crowd sourcing, voting, navigation, and many others. NFC technology enables the integration of services from a wide range of applications into one single smartphone. NFC technology has emerged recently, and consequently not much academic data are available yet, although the number of academic research studies carried out in the past two years has already surpassed the total number of the prior works combined. This paper presents the concept of NFC technology in a holistic approach from different perspectives, including hardware improvement and optimization, communication essentials and standards, applications, secure elements, privacy and security, usability analysis, and ecosystem and business issues. Further research opportunities in terms of the academic and business points of view are also explored and discussed at the end of each section. This comprehensive survey will be a valuable guide for researchers and academicians, as well as for business in the NFC technology and ecosystem.
Sensors | 2015
Busra Ozdenizci; Vedat Coskun; Kerem Ok
Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability.
IEEE Transactions on Mobile Computing | 2006
Vedat Coskun; Erdal Cayirci; Albert Levi; Serdar Sancak
The quarantine region scheme (QRS) is introduced to defend against spam attacks in wireless sensor networks where malicious antinodes frequently generate dummy spam messages to be relayed toward the sink. The aim of the attacker is the exhaustion of the sensor node batteries and the extra delay caused by processing the spam messages. Network-wide message authentication may solve this problem with a cost of cryptographic operations to be performed over all messages. QRS is designed to reduce this cost by applying authentication only whenever and wherever necessary. In QRS, the nodes that detect a nearby spam attack assume themselves to be in a quarantine region. This detection is performed by intermittent authentication checks. Once quarantined, a node continuously applies authentication measures until the spam attack ceases. In the QRS scheme, there is a trade-off between the resilience against spam attacks and the number of authentications. Our experiments show that, in the worst-case scenario that we considered, a not quarantined node catches 80 percent of the spam messages by authenticating only 50 percent of all messages that it processes
Wireless Personal Communications | 2006
Ayhan Erdogan; Vedat Coskun; Adnan Kavak
We introduce a novel sensor node management and location estimation method referred as sectoral sweeper (SS) scheme that uses an adaptive antenna array (AAA) at a central node in wireless sensor networks (WSNs). With the SS scheme, the central node can activate or deactivate the nodes in a desired region which is specified by beam direction and beam width of the transmit beam and also by minimum and maximum thresholds (Rmin and Rmax) for the received signal strength indicator (RSSI) of signals received by the nodes. In order to perform a specified task that is associated with a Task_id, two different beams are transmitted, which are task region beam and routing region beam to switch the nodes into active or routing modes. Since our scheme does not require any additional software or hardware for node management and location estimation in sensor nodes, the deficiencies of tiny sensors are effectively eliminated. The proposed scheme is shown to reduce the number of sensing nodes and the amount of data traffic in the network, thus leading to considerable savings in energy consumption and prolonged sensor lifetime.
military communications conference | 2004
Hakan Tezcan; Erdal Cayirci; Vedat Coskun
In this paper, a distributed scheme for three dimensional sensor space coverage in tactical underwater sensor networks is introduced. When sensor nodes are first deployed, sensors lie in surface buoys. After deployment, sensors are lowered to various depths selected by our scheme such that the maximum coverage of the three dimensional sensor space is maintained. Experiments show that our scheme maintains more than 90% coverage efficiency most of the time at the expense of acceptable control traffic overhead.
Wireless Personal Communications | 2013
Kerem Ok; Vedat Coskun; Busra Ozdenizci; Mehmet N. Aydin
Near Field Communication (NFC) is a short range wireless communication technology allowing to communicate mobile devices within close proximity. It provides opportunity for service providers to offer various value added services to customers. NFC technology allows the usage of wide range of applications and eliminates the obligation to carry additional components other than the mobile device such as credit or payment cards, tickets, identification cards or keys. Despite its technological advantages over alternative ones, the NFC business ecosystems and services are yet to take off. The problems mainly arise with the business issues triggered by different and mostly conflicting needs of many actors in the ecosystem and several additional technical issues. In this study, by adopting a role-based service ecosystem modeling, we propose an NFC ecosystem model which perfectly specifies the roles in the ecosystem, and defines set of activities for each role, and communication structure. We analyzed NFC ecosystem in three phases as pre-installation, installation, and service usage. We have defined the activities and communication structure in the first two phases, and finally investigated the service usage phase in three different operating modes of NFC. After giving the details of the proposed ecosystem model, two use cases are given to validate the developed ecosystem model. We complete our study by discussing the requirement satisfaction.
international conference on communications | 2004
Serdar Sancak; Erdal Cayirci; Vedat Coskun; Albert Levi
Anti-nodes deployed inside a wireless sensor network can frequently generate dummy data packets that make the nodes relaying them deplete their energy. Especially the nodes closer to the sink fail sooner, because they convey more data packets. This causes the sink to be disconnected from the sensor network. The counter-measures for this type of attacks, namely spam attacks, should consider that the sensor nodes have limited energy, computational power and memory. In this paper, we propose detect and defend against spams (DADS) scheme. In DADS the vicinity of the detected malicious node is notified about the quarantine region, and nodes do not relay unauthenticated messages coming from a node in the quarantine region. Our experiments show that our scheme fits the requirements of the sensor network.
Wireless Personal Communications | 2013
Busra Ozdenizci; Kerem Ok; Vedat Coskun
Near Field Communication (NFC) as an emerging technology is currently leveraged by large standardization efforts and tries to find a suitable ecosystem. NFC enabled mobile devices with integrated smart cards introduce compelling opportunities and new business models. Development of new standards such as secure element (SE), smart card, secure channel, as well as JavaCard enables creating new ecosystems using a concurrent multi application platform which takes advantage of GlobalPlatform standards. We proposed NFC Loyal, which maintains storage, retrieval, and sharing among payment and loyalty applications through our proposed structure, called as Secure Common Domain Management (SCDM) system. SCDM as a centralized database management system on the SE stores valuable information provided by payment applications and shares them with loyalty applications through a secure channel. The direct outcome of using NFC Loyal is the increase in repeat purchases of customers; as well as being a beneficial business plan realized among the payment firms, loyalty firms, and the card owner, resulting in a win-win business model. In this study, we describe NFC Loyal model with its technical infrastructure, and present the NFC Loyal model’s life cycle management on SE.