An Architectural Framework for Ubiquitous Computing Applications I. Koutelekos 1 Dpts. of Electronics and Automation MSc in Networking and Data Communications, T.E.I. of Piraeus, Greece, Email: ekoutele@otenet.gr This dissertation demonstrates the term Ubiquitous computing. Although it is a very general subject, it is attempting to inform and explain how can this works and which the parameters, the elements and the ingredients are required. Ubiquitous computing nowadays and in the future will be a common concept that will integrate all forms of technological innovation and technical improvements. There is the description of the environment of a ubiquitous computing, the modelling of the applications and the users. There is also a description on how the communication is achieved among the applications as well as some methods of middleware technology which could help in developing the applications and the ubiquitous computing. Further on, there are descriptions about the CORBA, DCOM and for WEB SERVICES technologies. Lastly, a solution is presented for faster user modelling and dealing the subject of new user requirements in a system. The solution is a theoretical scenario about how to locate information and find a match to a query in order to model a user or a context using information from systems with similar specifications. This presentation requires all the systems and those which probably are going to be created to have been connected with the internet. In this way any system would exchange information helping other systems to implement with ongoing modelling.
Content caching contributing to the Future Internet Architecture E.Koutsourakis 1 1 Dpts. of Electronics and Automation MSc in Networking and Data Communications, T.E.I. of Piraeus, Greece, Hellas Tel: +30 210 5381327, Fax: +30 2105451128, E-mail: dc-284@stef.teipir.gr, evko@mycosmos.gr In nowadays, the wide popularity of the Internet is a fact. This results to increased demands on infrastructure and direct response to end user s high premises. Fast Internet, as a mean to fast response time, no extensive delays by the side of the everyday user and good operative and maintenance conditions from the part of content management, is a dynamic and competitive issue. At this paper there will be an approach to content delivery networks from the beginning. A short look on the main protocols that are used in these networks will be performed; also the techniques that are used for the delivery of the content from source to destination will be approached and studied. There is a practical part that uses mainly the program OPNET IT GURU Academic edition for the evaluation of specific metrics. It is a suitable program for academic research that gives an analysis of a case study not necessarily implemented in real world but popularly used for experimental and testing purposes based on theoretical principles and facts. Keywords: Content, delivery, internet, delays.
Incident Identification System Based on Mobile Devices A. Latsas 1 1 Dpts. of Electronics and Automation MSc in Networking and Data Communications, T.E.I. of Piraeus, Greece, E-mail:dc-285@stef.teipir.gr In this paper an incident identification system is proposed. The system is consisted of a web based platform and mobile clients. Such a system could be used for detection of emergency events such as forest fires. It combines information from different users about a specific event, trying to locate it fast and accurately on the map. The incident location is assumed to be known only by approximation from the user's perspective. The system combines incident reports sent from the mobile clients and then analyzes them using a detection algorithm in order to locate the actual incident location.
OBJECTIVE IMAGE QUALITY ASSESSMENT Mazi Spyridoula 1 T.E.I. of Piraeus, Greece, E-mail: spyllam@gmail.com In multimedia communications the image quality is the most important factor of Quality of Experience (QoE). The quality is being measured using two methods: objective metrics which use algorithms and subjective metrics which use human evaluation. In this project the main types of objective image quality assessment [Peak Signal-to-Noise Ratio (PSNR), Structural Similarity Index Measure (SSIM) and Video Quality Metrics (VQM)] are about to be analysed compared to the main types of subjective metrics. It is also proved that if someone adapts the features of Human Vision System (HVS) in objective metrics then results can predict subjective scores. Finally, a new type of objective metrics is suggested which is called hybrid metrics and is being used especially in real-life applications. Index Terms Quality of Experience (QoE), Peak Signal-to-Noise Ratio (PSNR), Structural Similarity Index Measure (SSIM), Video Quality Metrics (VQM), Subjective Quality Assessment, Human Vision System (HVS), Hybrid Objective Metrics.
WEB SERVICES ORCHESTRATION IN SERVICE- ORIENTED ARCHITECTURE (SOA) ENVIRONMENTS T. Nikolakopoulou 1 T.E.I. of Piraeus, Greece,E-mail: theoninikol2@gmail.com In this paper we present Web Services Orchestration in Service-Oriented Architecture (SOA) Environments. Firstly, presents the SOA [1] concept and the basic details of technology. Additionally, in next section that examines the Web Services[3] technology. Moreover, in next section that presents and analyzes the basic concept of "Orchestration" and it studies the most common language that is being used by Web Services, that is BPEL[13]. Furthermore, in last chapter, that refers to an orchestration methodology where we present and analyze an event-driven implementation of the service orchestration engine which is built upon the event architecture and join patterns. 5
Operational Principles and Performance Evaluation of Routing Techniques in Wireless Sensor Networks A. Papageorgiou T.E.I. of Piraeus, Greece, E-mail: author1@myuniversity.edu WSNs are the key due to recent technological advances. Many routing protocols have been specifically designed for wireless sensor networks. In this thesis some of the routing techniques outline and present a survey of state-of-the-art in WSNs. Zigbee routing protocol is discussed in detail about its architecture, features and functionalities. The focus however, has been given to zigbee network analysis in a theoretical and not only survey. Furthermore, the above mentioned theoretical study is combined with a lab experiment. Overall, this project highlights the performance issues and conclusions as well possible future research areas. 6
DATABASE SECURITY ANALYSIS AND TESTING Piperakis Charalampos T.E.I. of Piraeus, Greece, Email: k1065769@kingston.ac.uk It is widely known that database security is the number one issue regarding web applications as the protection of data field is critical. Specifically due to the growth of networks organizations share their data through the internet and that appears to have both advantages and disadvantages. The advantages stand for the easiness of communication and exchange of data on the other hand appears to be the most vulnerable environment for databases. In this paper is described as wel as implemented one of the most common attacks in databases which is sql injection. The implementation is done with use of automated tools which are widely known as penetration tools. 7
Analysis of a video compression algorithm M. Plakia 1 T.E.I. of Piraeus, Greece, E-mail: mplakia@gmail.com In this paper we study the effects of MPEG compression on the digital video quality. Initially there is an introduction to the MPEG compression standard, and in particular the MPEG-1, MPEG-2 and MPEG-3 standards are presented. Section 3 describes the method of motion estimation which is used at video digitization and the block matching algorithms which were developed to fulfill the operation of motion estimation. Finally, in section 4 the MATLAB code of the PSNR algorithm, which is used for the objective quality assessment of the compressed digital video is described. Moreover, a MATLAB code is analyzed for the evaluation of MPEG video compression using motion estimation. By this way we tried to conduct some PSNR results, of the Exhaustive Search, the Three Step Search, the Diamond Search and the Adaptive Root Pattern Search algorithm. 8
Experimental performance study of the IEEE 802.15.4 MAC layer Dimitrios Sakavalas 1 T.E.I. of Piraeus, Greece, E-mail:sakavalas@gmail.com Zigbee wireless sensors networks WSNs are a new upcoming technology that combines very good performance with low rate, and first are setting up for use on industry. Other sectors in which the WSNs are used, are smart energy, health care, telecom services, smart buildings, internet of things etc. The WSNs make use of the ZigBee protocol (APS, Zigbee NWK, ZDO) that is the higher layer for communication combined with the IEEE 802.15.4 protocol (MAC layer, PHY layer). This technology has to overcome some critical obstacles such as power consumption, network robustness and scalability, throughput rate, security, that are some of the critical performance parameters of the network. IEEE 802.15.4 MAC layer protocol is the core layer of WSNs and it performance plays a significant role in terms of determining the network performance parameters that mentioned above. In this thesis, the project aims to present the operational principles of 802.15.4 MAC layer protocol from the slotted CSMA/CA viewpoint, which is currently adapted in ZigBee Wireless Sensor Networks. 9
Modulation formats for optical fiber transmission Aggeliki Thomopoulou In the past years there has been a wide improvement in the field of optical communications motivated by the higher demand of bandwidth due to the increase of data traffic. Thus, alternative modulation formats have been employed in order to enhance the impairments of traditional modulation formats like the on-off keying in either non-return to zero (NRZ) and return to zero (RZ) formats. The growing requirement of achieving higher bit rates and improve the spectral efficiency of optical transmission systems, has opened the door to new advanced modulation formats which carry the information both in their optical amplitude and phase, in order to enhance the robustness to chromatic dispersion, optical filtering and nonlinearities. The purpose of this project is to review wellestablished technologies and current trends in the optical modulation formats. For this reason, the properties of the optical fibers will be studied along with the components that modern optical communication systems consist of. Following, the performance of the traditional amplitude modulation formats will be thoroughly examined and then the alternative modulation formats (for example AMI, CRZ, CSRZ, PSK, DPSK, QPSK) will be introduced; the emphasis on the latter will be placed in their relative performance boost to the former. This study will conclude with a comparison of the presented modulation formats in terms of their complexity and required bandwidth 10
Cross layer design for wireless video transmission panorama of approaches C. Dounis 1, A. Papadakis 2 T.E.I. of Piraeus, Greece, Email: dounisharris@yahoo.gr 2 Dpts. of Electronics and Automation MSc in Networking and Data Communications, T.E.I. of Piraeus, Greece, Email: andreas.papadakis@gmail.com CDN architectures perform content replication caching (mainly at the edges of the network). Content Distribution Networks consist of groups of intermediate servers (Proxy-servers) placed in key positions on the Internet. In parallel, the Internet of the Future is tightly coupled with the Cloud. The Cloud comprises of distributed data centers, which offer economies of scale, and cheaper computing resources. In the current paper we present a comparative analysis of business models in the area of content distribution, namely models used by content distributors, who are responsible for the operation of the CDN. The goal is to study how robust and effective is the solution of using the Cloud for content replication and distribution. 11
Information Centric Networking: Investigating the future of internet and its applications. Pavlakis Demosthenis 1 T.E.I. of Piraeus, Greece, E-mail:demosthenes_p@hotmail.com 12
Operational Principles and Performance Evaluation of Routing Techniques in Wireless Sensor Networks, A. Papageorgiou, S. Savvaidis 13