P2P Systems

Since the turn of the century, the discipline of design has increasingly focused its attention on its ap- plication to projects and groups of users at a larger scale. Researchers and practitioners have tried to understand how design could shift its focus from single users to local and online communities, from isolated projects to whole complex systems. These new perspectives consequently brought the inter- est of designers to the tools and strategies that can enable their interactions with larger groups of people distributed in several localities. More specifically, designers and researchers started adopting many approaches coming from software development and web-based technologies, like open source, P2P, diffuse, distributed and decentralized systems. This article proposes a preliminary framework for understanding and working with the integration of design with open, P2P, diffuse, distributed and de- centralized systems. In one direction, such open, P2P, DDD systems can be applied into design practice: this first intersection has many applications, from digital projects to P2P-based initiatives to physi- cal projects designed and manufactured on global networks of distributed laboratories like Fab Labs and Makerspaces. In another direction, design practice can also have a role in enabling such systems through the analysis, visualization, and design of their collaborative tools, platforms, processes, and organizations. Design, therefore, could learn from such systems and also improve them. This second in- tersection falls into the meta-design domain, where designers can have a role in building environments for the collaborative design of open processes and their resulting organizations.
The article therefore addresses this phenomenon by providing both an analysis of the concepts and the history of both directions and, in order to understand the phenomena with a broader overview, it proposes a preliminary framework for understanding the possible intersections of design with open, P2P, diffuse, distributed and decentralized systems through both literature and case studies. As the framework is still preliminary, the article provides as a conclusion some possible strategies for validat- ing or improving the framework.

Peer-to-Peer  (P2P)  systems  allow  decentralization,  sharing  of  all  the  resources  of  a  network  with  direct
communication  and  collaboration  between  nodes.  There  are  three  main  families  of  P2P  networks:  the
centralized  architecture,  the  decentralized  architecture  that  can  be  structured  or  unstructured  and  the
hybrid  architecture.  Today,  there  are  several  implementations  for  structured  decentralized  architectures.
This  implies  that the  insertion  and  search  algorithms  are different. Among them  we  have;  Chord,  Pastry, 
Kademlia, CAN(Content Addressable Network) . The choice of these DHTs (Distributed Hash Table) for an
application is made on the basis of their performances. Studies of each of these DHTs mentioned have been
done, proving their performance. But a comparative study of the four DHTs Chord, Pastry, CAN, Kademlia
has  not  been  clearly  addressed  by  previous  works.  In  this  paper,  we  have  conducted  a  comparative
theoretical study of the DHTs Chord, Pastry, CAN, Kademlia. Then, by simulation, we have evaluated the
performances in terms of latency, number of hops and number of transmitted messages. Our study clearly
shows  the  differences  between  mathematically  established  performance  and  actual  performance  in  an
environment  with  less  restriction.  This  analysis  was  made  from  the  data  obtained  by  using  the  simple
network  layer  of  the  PeerfactSim  simulator.  This  simulator  abstracts  the  different  network  layers,  which
gives  the  advantage of testing the  performances  with  reasonable  accuracy.  The use  of  the  single  network
layer can be considered an ideal case because the node searches are done locally.

Mobile  Ad-hoc  networks  are  categorized  by  multi-hop  wireless  connectivity  and  numbers  of  nodes  are
connecting each other through wireless network. It includes several routing protocols specifically designed
for ad-hoc routing. The most widely used ad hoc routing protocols are Ad-hoc On Demand Distance Vector
(AODV),  Destination  Sequence  Distance  Vector  (DSDV),  and  Dynamic  Source  Routing  (DSR).  In  this
paper, we present an  analysis of DSR protocol and propose our algorithm to improve the performance of
DSR protocol by using small delay applied on last route ACK path when an original route fails in Mobile
Ad  Hoc  networks.  Past  researchers  the  MANET  have  focused  on  simulation  study  by  varying  network
parameters, such as network size, number of nodes. The simulation results shows that the M-DSR protocol
having  some  excellent  performance  Metrics  then  other  protocols.  We  have  taken  different  performance
parameters over the  comparison  of  Modified -DSR  with  other three  protocols in mobility as  well  as Non-
mobility scenario up to 300 nodes in MANETs using NS2 simulator. To achieve this goal DSR is modified
by  using  modified  algorithm  technique  in  order  to  load  balancing,  to  avoid  congestion  and  lower  packet
delivery.

The International Journal of peer-to-peer networking is a quarterly open access peer-reviewed journal that publishes articles that contribute new results in all areas of P2P Networks. The journal provides a platform to disseminate new ideas and new research, advance theories, and propagate best practices in the area of P2P networking. This will include works that relate to peer-to-peer systems, peer-to-peer applications, grid systems, large-scale distributed systems, and overlay networks. The journal offers a forum in which academics, consultants, and practitioners in a variety of fields can exchange ideas to further research and improve practices in all areas of P2P.

This article examines the bitcoin, at present the most popular cryptocurrency. The bitcoin grew on the major pillars of the neoliberal market economy, such as liberalization, deregulation and privatization. But in the end, it turned out to be a cure for the dysfunctions of the financial system, which was based on neoliberal assumptions. The difficulty in capturing the character and status of the bitcoin still makes it elusive for the existing rules of law. Some governments observe the evolution of the bitcoin market with interest; others try to work against it. All of this makes the bitcoin an intriguing subject for research. The aim of this article is to present the original assumptions of the bitcoin system; trace the reactions to the bitcoin’s emergence in virtual reality, and next on the very real financial market; and analyze the reinterpretation of the idea that underlies the creation of the cryptocurrency. This article attempts to assess the bitcoin’s potential of achieving a seemingly impregnable position on the global financial market.

keywords: technology, p2p technology, economic democracy, crypthocurrencies

Manufacturing in areas of the developing world that lack electricity severely restricts the technical sophistication of what is produced. More than a billion people with no access to electricity still have access to some imported higher-technologies; however, these often lack customization and often appropriateness for their community. Open source appropriate technology (OSAT) can over­come this challenge, but one of the key impediments to the more rapid development and distri­bution of OSAT is the lack of means of production beyond a specific technical complexity. This study designs and demonstrates the technical viability of two open-source mobile digital manufacturing facilities powered with solar photovoltaics, and capable of printing customizable OSAT in any com­munity with access to sunlight. The first, designed for com­munity use, such as in schools or maker­spaces, is semi-mobile and capable of nearly continuous 3-D printing using RepRap technology, while also powering multiple computers. The second design, which can be completely packed into a standard suitcase, allows for specialist travel from community to community to provide the ability to custom manufacture OSAT as needed, anywhere. These designs not only bring the possibility of complex manufacturing and replacement part fabrication to isolated rural communities lacking access to the electric grid, but they also offer the opportunity to leap-frog the entire conventional manufacturing supply chain, while radically reducing both the cost and the environmental impact of products for developing communities.

The International Journal of peer-to-peer networking is a quarterly open access peer-reviewed journal that publishes articles that contribute new results in all areas of P2P Networks. The journal provides a platform to disseminate new ideas and new research, advance theories, and propagate best practices in the area of P2P networking. This will include works that relate to peer-to-peer systems, peer-to-peer applications, grid systems, large-scale distributed systems, and overlay networks. The journal offers a forum in which academics, consultants, and practitioners in a variety of fields can exchange ideas to further research and improve practices in all areas of P2P. Authors are solicited to contribute to the journal by submitting articles that illustrate research results, projects, surveying works and industrial experiences that describe significant advances in the areas of P2P networks.

In Ciphertext Policy Attribute based Encryption scheme, the encryptor can fix the policy, who can decrypt the encrypted message. The policy can be formed with the help of attributes. In CP-ABE, access policy is sent along with the ciphertext. We propose a method in which the access policy need not be sent along with the ciphertext, by which we are able to preserve the privacy of the encryptor. The proposed construction is provably secure under Decision Bilinear Diffe-Hellman assumption.

In recent years, the increasing concerns around the centralized cloud web services (e.g. privacy, governance, surveillance, security) have triggered the emergence of new distributed technologies, such as IPFS or the Blockchain. These innovations have tackled technical challenges that were unresolved until their appearance. Existing models of peer-to-peer systems need a revision to cover the spectrum of potential systems that can be now implemented as peer-to-peer systems. This work presents a framework to build these systems. It uses an agent-oriented approach in an open environment where agents have only partial information of the system data. The proposal covers data access, data discovery and data trust in peer-to-peer systems where different actors may interact. Moreover , the framework proposes a distributed architecture for these open systems, and provides guidelines to decide in which cases Blockchain technology may be required, or when other technologies may be sufficient.

This part of the “Grundrisse” has been object of many different interpretations of what Marx really wanted to say with “general intellect”. Most of these interpretations understand it like a synonym of swarm intelligence or stigmergy. In other word, types of distributed intelligence that emerges from interaction of parts of the system which operate independently, non-systemic, only on the basis of some very elementary instructions that can be executed at the individual level.
I immediately say what I think: intelligence is always “swarm” and does not exist a non-diffused intelligence. Nevertheless, the Marxian general intellect it is another thing and it is not “swarm” because it is the science of the system, not the intelligence of the system.
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NOTE: I originally wrote this article in Italian and then I tried to translate it into English as best I could, in order to give a chance to read also to those who do not speak Italian. Unfortunately my English is far from being correct, then it is very likely that there are errors. I apologize for this in advance.

The International Journal of peer-to-peer networking is a quarterly open access peer-reviewed journal that publishes articles that contribute new results in all areas of P2P Networks. The journal provides a platform to disseminate new ideas and new research, advance theories, and propagate best practices in the area of P2P networking. This will include works that relate to peer-to-peer systems, peer-to-peer applications, grid systems, large-scale distributed systems, and overlay networks. The journal offers a forum in which academics, consultants, and practitioners in a variety of fields can exchange ideas to further research and improve practices in all areas of P2P.

P2P mesh-pull live video streaming applications – such as CoolStreaming, PPLive, and PPStream – have become popular in the recent years. In this paper, we examine the stream pollution attack, for which the attacker mixes polluted chunks into the P2P distribution, degrading the quality of the rendered media at the receivers. Polluted chunks received by an unsuspecting peer not only effect that single peer, but since the peer also forwards chunks to other peers, and those peers in turn forward chunks to more peers, the polluted content can potentially spread through much of the P2P network. The contribution of this paper is twofold. First, by way of experimenting and measuring a popular P2P live video streaming system, we demonstrate that the pollution attack can be devastating. Second, we evaluate the applicability of four possible defenses to the pollution attack: blacklisting, traffic encryption, hash verification, and chunk signing. Among these, we conclude that the chunk signing solutions are most suitable.

Intelligent products are an undeniable asset for efficient product lifecycle management (PLM), providing ways to capture events related to physical objects at various locations and times. Today and more than ever before, PLM tools and systems must be built upon standards for enhancing interoperability among all product stakeholders and developing tools independent of specific vendors, applications, and operating systems. Based on this observation, this paper develops strategies to improve « information sustainability » in PLM environments using standardized communication interfaces defined by a recent standard proposal named quantum lifecycle management (QLM) messaging standards. More concretely, data synchronization models based upon QLM standards are developed to enable the synchronization of product-related information among various systems, networks, and organizations involved throughout the product lifecycle. Our proposals are implemented and assessed based on two distinct platforms defined in the healthcare and home automation sectors.

3rd International Conference on Machine learning and Cloud Computing (MLCL 2022) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Cloud computing. The aim of the conference is to provide a platform to the researchers and practitioners from both academia as well as industry to meet and share cutting-edge development in the field.
This conference aims to bring together researchers and practitioners in all aspects of machine learning and cloud-centric and outsourced computing, including (but not limited to):

P2P applications suffer from free-riding. In
economics terminology, free-riding is the rational
behavior of the participants. So it’s feasible to use
game theory to analyze this problem and design
countermeasures. Tit-for-Tat is a simple and efficient
equilibrium strategy in repeated game environments.
In this paper, we construct a game model in P2P
environments and deduce the constraint under which
the strict Tit-for-Tat is an equilibrium strategy. We
then improve and adapt the Tit-for-Tat strategy to the
dynamic property in P2P networks, and deduce the
constraint under which it is still an equilibrium
strategy. Finally we study through simulations the
performance improvement of the enhanced Tit-for-Tat
and give suggestion of how to choose proper system
parameters under different network conditions.

What is the participatory map, and when did it emerge? In the online world, we're in the middle of a renaissance of popular cartography, enabled by big data and the comparative cheapness of distributing graphic information on the web. Some of these maps-including some maps enabled by platforms like Google Maps, Open Street Map, or Ushahidi-are compiled by many individuals, working atop a digital infrastructure that enables the contribution of specific place-names, topographical features, social data, or real-time observations (for instance, of police movements, natural disasters, sexual assault, ecological contamination, or political corruption), all collected into a single interface that makes for easy analysis (

Makerspaces and their various declinations are a widespread initiative of workshops that offer open access to digital and traditional production equipment, with the aim of democratizing access to technologies and supporting bottom-up innovation. They are recognized as a new form of ‘third places’ in a contemporary perspective. As the number of such places grows along with their active communities, business models, contamination projects with universities, companies, and civil society, many researchers have explored the ability of makerspaces to serve as innovation facilitators. Over the last few years, networks and coalitions of makerspaces have started to pop-up with a range of objectives, such as the advocacy and coordination of territorial or project-oriented coalitions; however, they remain largely unanalyzed and undocumented. The paper explores the phenomenon of these networks, drawing on a case study that describes the development of a makerspace regional network in Northern Italy, providing insights concerning its impact on both relationships at a local level and on the acceptance of third places within a regional innovation system, contributing to opening a new field of discussion about the potential of such networked organizations.

The classic mutual exclusion problem in distributed systems occurs when only one process should access a shared resource. Various algorithms are proposed in order to solve this problem. When using a permission based approach which consist in exchanging permission messages to grant access to the critical resource, less messages should be sent over the network because bandwidth consumption and synchronization delay
should be reduced. Richa, shikha and Pooja proposed an algorithm using nodes logically organized in a complete binary tree. This algorithm called NTBCBT requires 4log2(N) messages per access to critical section and a synchronization delay of 3log2(N) for a set of N nodes competing for the critical ressource. In this paper, we study NTBCBT and we show that this algorithm has problems related with safety, liveness
and scheduling. We improve this algorithm by correcting these weaknesses. Moreover, our algorithm requires 3log(N) messages per access to critical section and a synchronization delay of 2log(N). This improvement is due to the removal of useless messages, a reorganization of instructions on each node and an insertion of access requests using their timestamp.

Peer-to-Peer (P2P) systems have the ability to bond with millions of clients in business and knowledge scenario. The mechanism that leads users to distribute files without the need of centralized servers has achieved wide recognition among internet users. This also permits for a range of applications further than simple file sharing. he main problem lies in the fact that peers have to customarily intermingle with
mysterious peers in the absence of trusted third parties. Usually the lack of incentives often makes these
strange peers to act as freeriders and thus reduce the system performance. The trustworthiness among peers is portrayed by applying the knowledge obtained as a result of reputation mechanisms. This paper endows with a new reputation model in association with a detailed survey of diverse reputation models. The proposed model suggests a hybrid reputation model through dynamic regrouping.

It is well known that content distribution networks (CDN) are expensive technologies for distributing web contents. Universities and other non-profit organizations do not have enough financial means to deploy large web-servers or to use content distribution networks to improve their web access performance. A current trend is to use hybrid distribution networks content. so this article is to show the efficiency of P2P networks possessing this approach.

The International Journal of peer-to-peer networking is a quarterly open access peer-reviewed journal that publishes articles that contribute new results in all areas of P2P Networks. The journal provides a platform to disseminate new ideas and new research, advance theories, and propagate best practices in the area of P2P networking. This will include works that relate to peer-to-peer systems, peer-to-peer applications, grid systems, large-scale distributed systems, and overlay networks. The journal offers a forum in which academics, consultants, and practitioners in a variety of fields can exchange ideas to further research and improve practices in all areas of P2P.

This paper aims to shed light on a transversal phenomenon, as it affects both the scope of the law and the technology, ethics and certain legally recognized rights. This is the impact that the deep packet inspection technology has in the current internet. Through this technological innovation, effectively used nowadays, the ISPs (Internet service providers) can analyze the content of what passes through their networks, treating it differentially if necessary. Thus, the proposed equal network may be truncated as these companies can monitor traffic on the network (determining a speed limit, prioritizing some connections or just banning them because of the data they are transmitting). In this paper, we analyze the impact that this technology can have in a very specific area, the copyright legislation, revealing the intense battle being waged between technology companies and the owners of intellectual property rights. We also discuss how this technology can subvert what the internet is becoming and, finally, how the role of the state is important in the regulation of the technology, for it will determine the interrelationship between technology and society.

Steganography is a technology used since years for the communication of messages secretly. These secret messages are put inside honest carriers. Carriers can be digital images, audio files, video files and so on. The limitation in sending concealed longer messages has been overcoming by the inclusion of video files as carriers. Popular internet services such as Skype, BitTorrent, Google Suggest, and WLANs are targets of information hiding techniques. Nowadays, plotters are not only using the carriers but also the protocols for communication that regulate the path of the carrier through the
Internet. This technique is named Network Steganography.

Distributed Hash Tables (DHTs) have been used in several applications, but most DHTs have opted to solve lookups with multiple hops, to minimize bandwidth costs while sacrificing lookup latency. This paper presents D1HT, an original DHT which has a peer-to-peer and self-organizing architecture and maximizes lookup performance with reasonable maintenance traffic, and a Quarantine mechanism to reduce overheads caused by volatile peers. We implemented both D1HT and a prominent single-hop DHT, and we performed an extensive and highly representative DHT experimental comparison, followed by complementary analytical studies. In comparison with current single-hop DHTs, our results showed that D1HT consistently had the lowest bandwidth requirements, with typical reductions of up to one order of magnitude, and that D1HT could be used even in popular Internet applications with millions of users. In addition, we ran the first latency experiments comparing DHTs to directory servers, which revealed that D1HT can achieve latencies equivalent to or better than a directory server, and confirmed its greater scalability properties. Overall, our extensive set of results allowed us to conclude that D1HT can provide a very effective solution for a broad range of environments, from large-scale corporate datacenters to widely deployed Internet applications 1,2 .

In large scale peer-to-peer networks, it is impossible to perform a query request by visiting all peers. There are some works that try to find the location of resources probabilistically (i.e. non-deterministically). They all have used inefficient protocols for finding the probable location of peers who manage the resources. This paper presents a more efficient protocol that is proximity-aware in the sense that it is able to cache and replicate the popular queries proportional to distance latency. The protocol dictates that the farther the resources are located from the origin of a query, the more should be the probability of their replication in the caches of intermediate peers. We have validated the proposed distributed caching scheme by running it on a simulated peer-to-peer network using the well-known Gnutella system parameters. The simulation results show that the proximity-aware distributed caching can improve the efficiency of peer-to-peer resource location services.

La FAO est convaincue que l’innovation, en général et en particulier dans le domaine de l'agriculture, est la force motrice essentielle pour parvenir à un monde libéré de la faim et de la malnutrition.L'innovation est généralement perçue comme étant liée à la technologie. En fait, la définition de l'innovation est beaucoup plus large.
L'innovation agricole est le processus par lequel des individus ou des organisations mettent en œuvre pour la première fois des produits, des processus ou des modes d'organisation nouveaux ou existants, dans un contexte spécifique, afin d'accroître l'efficacité, la compétitivité et la résilience dans le but de résoudre un problème.
La FAO joue un rôle clé dans la défense de l'importance de l'innovation en agriculture pour accroître la sécurité alimentaire, le développement durable et promouvoir le développement rural.
L'innovation dans l'agriculture touche toutes les dimensions du cycle de production et l'ensemble de la chaîne de valeur - de la production agricole, forestière, halieutique ou animale à la gestion des intrants et jusqu'à l'accès au marché.
La FAO aide les États membres à libérer le potentiel de l'innovation pour stimuler la croissance socio-économique, assurer la sécurité alimentaire et nutritionnelle, réduire la pauvreté et améliorer la résilience au changement climatique, contribuant ainsi à la réalisation des Objectifs de développement durable. Parce que l'innovation est un processus complexe dans lequel les gouvernements et d'autres acteurs clés jouent des rôles différents, la FAO privilégie une approche systémique.
Dans cet essai, nous examinons l'écosystème de l'agriculture P2P et Blockchains

The massive consumer often has security concerns about Internet transmissions, and the remote access of the IP Camera is also full of challenges from the consumer market for privacy and security. In this context, when the user account of the security monitoring system is maliciously used, the security protection mechanism provided by the IP Camera itself is one of the topics most concerned to consumers. In order to improve the security of the remote connection of IP Camera, based on SIP protocol and practical experience, this study designs a set of feasible processes for the management of public key, which will help consumers protect their privacy rights in using the security monitoring system and the security when remotely operating the IP Camera. Finally, the experiment results prove that it will not impact the users’ experience when accessing the IP Camera remotely.

Los sistemas P2P han adquirido en los últimos años una importancia extraordinaria entre los usuarios que comparten obras protegidas por derechos de explotación en exclusiva. El Código penal ha seguido el sentido que le marca la legislación civil, y pretende proteger los derechos de explotación en exclusiva impidiendo por todos los medios el pirateo de las obras protegidas. Con la intención de castigar a quienes se enriquecen con el negocio del pirateo, la ampliación típica de la última reforma penal sería capaz, también, de criminalizar las conductas de los sujetos usuarios P2P. La doctrina y la jurisprudencia vienen considerando que, en esos entornos comunicativos, no se da el ánimo de beneficio económico, pero esta es una perspectiva coyuntural. Ante el riesgo de que se active una criminalización de las conductas de los usuarios de redes P2P, el artículo propone algunas hipótesis para evitar su punibilidad, basadas en las características especiales de estos escenarios criminológicos. Pone la atención, para ello, en las peculiaridades que se dan en estos contextos en las relaciones de causalidad, en los objetos materiales y, sobre todo, en la adecuación social de las conductas.

The growth of small devices using as cell phones and smartphones has requested for the development of applications in different areas. The users may perform different tasks in these devices as read e-mails and magazines, make financial transactions, share physical resources, software and data, access multimedia content, and enjoy a variety of other applications. The diversity of mobile communication scenarios brings up the needs for applications to access not only Internet services but also local applications. This kind of application demands for a local communication, called collaborative communication, between the devices without the the usage of Internet infrastructure. This scenario represents a peer-to-peer (P2P) network, which allows the sharing and the exchanging of hardware, software and content. The content includes not only objects as musics, texts and videos, but also data about interests of the user. In the e-learning area this is not different and these applications potentially attract the students’ attention. Considering the user preferences and interest, the application may suggest suitable content to the student, motivating him during the learning-teaching interaction. The goal of this work is to propose a mobile P2P collaborative communication approach to allow the sharing and the exchanging of learning objects comparing their metadata to the student learning profile. The learning profiles are split into dimensions based on Felder and Silverman model to attend different student preferences. A prototype based on the proposed approach was developed to validate our architecture. We performed the architecture evaluation with 20 students of an undergraduate course. An evaluation using different message protocols was conducted to verify the proposal and suggest the best communication technology.The communication technology has an impact on the time spent during the exchange of objects which may interfere in the student motivation.

7 th International Conference on Data Mining and Database Management Systems (DMDBS 2021) provides a forum for researchers who address this issue and to present their work in a peer-reviewed forum. Authors are solicited to contribute to the conference by submitting articles that illustrate research results, projects, surveying works and industrial experiences that describe significant advances in Data mining and Applications.

Peer-to-Peer  (P2P)  networking  emerged  as  a  disruptive  business  model  displacing  the  server  based
networks  within  a  point  in  time.P2P  technologies  are  on  the  edge  of  becoming  all-purpose  in  developing
several  applications  for  social  networking.  In  the  past  seventeen  years,  research  on  P2P  computing  and
systems has received enormous amount of attention in the areas of academia and the industry. P2P rose to
triumphant  profit-making  systems  in  the  internet.  It  represents  the  best  incarnation  of  the  end  to  end
argument, the frequently disputed  design philosophies that  guided the design of the internet. The doubting
factor then  is  why is research on P2P computing  now fading  from the spotlight  and suffering  a  nose  dive
fall  as  dramatic  as its  rise to  its  popularity. This paper  is  going  to capture  a quick  look  at  past results in
peer-to-peer computing with focus on understanding what led to its rise, what contributed to its commercial
success and  what  has led to its lack  of interest. The insight of this paper introduces cloud computing  as  a
paradigm to peer-to-peer computing.

An intrusion detection system plays a major role in network security. We propose a model "DB-OLS: An Approach for IDS" which is a Deviation Based-Outlier approach for Intrusion detection using Self Organizing Maps. In this model "Self Organizing Map" approach is to be used for behavior learning and "Outlier mining" approach, for detecting an intruder by calculating deviation from known user profile. This model aims to improve the capability of detecting intruders.

Wireless sensor network are emerging in various fields like environmental monitoring, mining, surveillance system, medical monitoring. LEACH protocol is one of the predominantly used clustering routing protocols in wireless sensor networks. In Leach each node has equal chance to become a cluster head which make the energy dissipated of each node be moderately balanced. We have pioneered an improved algorithm named as Novel Leach based on Leach protocol. The proposed algorithm shows the significant improvement in network lifetime .Comparison of proposed algorithm is done with basic leach in terms of network life time, cluster head selection, energy consumption, and data transmission to base station. The simulation results shows that proposed algorithm can reduce network energy consumption and prolong network life commendably. Simulation of our protocol is done with Matlab.

In the last decade Peer to Peer technology has been thoroughly explored, becauseit overcomes many limitations compared to the traditional client server paradigm. Despite its advantages over a traditional approach, the ubiquitous availability of high speed, high bandwidth and low latency networks has supported the traditional client-server paradigm. Recently, however, the surge of streaming services has spawned renewed interest in Peer to Peer technologies. In addition, services like geolocation databases and browser technologies like Web-RTC make a hybrid approach attractive. In this paper we present algorithms for the construction and the maintenance of a hybrid P2P overlay multicast tree based on topological distances. The essential idea of these algorithms is to build a multicast tree by choosing neighbours close to each other. The topological distances can be easily obtained by the browser using the geolocation API. Thus the implementation of algorithms can be done web-based in a distributed manner. We present proofs of our algorithms as well as experimental results and evaluations.

Estas notas que siguen las escribimos al rebufo de las primeras sentencias civiles (1) que, en España, han enjuiciado la responsabilidad de sendos usuarios de redes P2P por sus posibles conductas contrarias a la regulación de la propiedad intelectual (2). El objetivo de estos comentarios, sin embargo, no pasa por estirar las interpretaciones judiciales expuestas en las sentencias para proyectarlas, sin filtros, al ámbito penal; no insinuamos que de estas interpretaciones de la ley civil se desprendan, necesariamente, consecuencias en el plano penal; pero sí notamos que con las argumentaciones expuestas en estas sentencias se abre un campo de posibilidad hacia ciertas implicaciones penales. Dicho de otro modo: no planteamos deducciones normativas lógicas con fuerza legal o jurisprudencial; pretendemos, tan solo, dar resonancia a las lógicas que explican jurídicamente la realidad de la compartimentación en red y que empiezan a transitar nuestros juzgados para, así, sondear el sentido de la punibilidad posible, de la reprobación penal que sobrevuela a los sujetos usuarios de redes P2P, sobre todo tras la reforma de 2015. Porque las redes P2P esbozan un campo criminológico que, sin duda, será central en los próximos años. Las prestaciones tecnológicas que ofrecen son el mejor aval para esta hipótesis, ya que la estructura en red parece la más apta para el intercambio informacional, optimizando el acceso a los datos mediante la evitación de servidores centrales (3). Sin embargo, estas complejidades tecnológicas tienen su reverso en las sombras jurídicas que arrojan, ya que las programaciones que sirven como base para la comunicación entre pares disponen un campo de acción cruzado y esquivo –casi como sublimación de inciertos no lugares (4) – que los sujetos transitan en modos difíciles de conceptuar jurídicamente. La arquitectura de relación electrónica entre pares dispone posibilidades de comunicación/acción e interacción caracterizadas por acciones previas de otros (programaciones) que activan no ya solo protocolos automatizados, sino acciones coetáneas de otros sujetos conectados. Y, en esa tesitura, el esclarecimiento de responsabilidades es dificultoso. No parece que haya impedimentos expresos para subsumir en los supuestos reprobatorios del Código penal la lesión de derechos de explotación en exclusiva de la propiedad intelectual a través de redes P2P: las conductas de reproducción o comunicación pública, importadas de la Ley de Propiedad Intelectual (5) (en adelante LPI), parecen encajar en la actividad desarrollada por usuarios P2P (6) ; sin embargo, nunca se ha castigado penalmente la conducta de un usuario P2P por un delito relativo a la propiedad intelectual. Desde un punto de vista teórico, la Fiscalía General del Estado —en sendas circulares (1/2006 (LA LEY 69/2006) y 8/2015 (LA LEY 387/2015))—, así como el propio Ministerio de Justicia (7) , consideran que las conductas previstas en el art. 270 del Código penal (en adelante

Recently there has been an effort to build scalable and reliable application-level multicast solutions that combine the resilience of pure gossip-based with the efficiency of tree-based schemes. However, such solutions assume that participants have unlimited resources, for instance, that they can send an unbounded number of messages to mask network omissions. Such scenario is not realistic, specially for streaming protocols, where messages can be transmitted at a very high rate and have a small temporal validity.

In this paper, we propose RASM, a scalable distributed protocol for application-level multicast. Our protocol is based on the combination of gossip-based and tree-based multicast schemes. Unlike previous approaches, which strive to combine gossip-based and tree-based schemes, our solution takes into consideration the reliability of components: nodes and communication links can fail, unexpectedly, ceasing their operation and dropping messages, respectively. Experimental results show that our scheme offers better reliability than previous solutions with low overhead.

Peer-to-peer systems have recently a remarkable success in the social, academic, and commercial communities. A fundamental problem in Peer-to-Peer systems is how to efficiently locate appropriate peers to answer a specific query (Query Routing Problem). A lot of approaches have been carried out to enhance search result quality as well as to reduce network overhead. Recently, researches focus on methods based on query-oriented routing indices. These methods utilize the historical information of past queries and query hits to build a local knowledge base per peer, which represents the user's interests or profile. When a peer forwards a given query, it evaluates the query against its local knowledge base in order to select a set of relevant peers to whom the query will be routed. Usually, an insufficient number of relevant peers is selected from the current peer's local knowledge base thus a broadcast search is investigated which badly affects the approach efficiency. To tackle this problem, we introduce a novel method that clusters peers having similar interests. It exploits not only the current peer's knowledge base but also that of the others in the cluster to extract relevant peers. We implemented the proposed approach, and tested (i) its retrieval effectiveness in terms of recall and precision, (ii) its search cost in terms of messages traffic and visited peers number. Experimental results show that our approach improves the recall and precision metrics while reducing dramatically messages traffic.

Commutative Replicated Data Type (CRDT) is a convergence philosophy invented as a new generation of technique that ensures consistency maintenance of replica in collaborative editors without any difficulty over Peer-to-Peer (P2P) networks. This technique has been successfully applied to different data representation types in scalable collaborative editing for linear, tree document structure and semi-structured data types but not yet on set data type ensuring Causality, Consistency and Intention (CCI) preservation criteria. In this paper, we propose a srCE approach, a novel CRDT for a set structure to facilitate the collaborative and concurrent editing of Resource Description Framework (RDF) stores in large scale by different members of virtual community. Our approach ensures CCI model and is not tied to a specific case and therefore can be applied for any document that complies to set structure. A prototype implementation using Friend of a Friend (FOAF) data sets with and without the srCE model illustrates significant improvement in scalability and performance.