Is Content Publishing in BitTorrent Altruistic or Profit-Driven

BitTorrent is the most popular P2P content delivery application where individual users share various type of content with tens of thousands of other users. The growing popularity of BitTorrent is primarily due to the availability of valuable content without any cost for the consumers. However, apart from required resources, publishing (sharing) valuable (and often copyrighted) content has serious legal implications for user who publish the material (or publishers). This raises a question that whether (at least major) content publishers behave in an altruistic fashion or have other incentives such as financial. In this study, we identify the content publishers of more than 55k torrents in 2 major BitTorrent portals and examine their behavior. We demonstrate that a small fraction of publishers are responsible for 66% of published content and 75% of the downloads. Our investigations reveal that these major publishers respond to two different profiles. On one hand, antipiracy agencies and malicious publishers publish a large amount of fake files to protect copyrighted content and spread malware respectively. On the other hand, content publishing in BitTorrent is largely driven by companies with financial incentive. Therefore, if these companies lose their interest or are unable to publish content, BitTorrent traffic/portals may disappear or at least their associated traffic will significantly reduce

Juno:An adaptive delivery-centric middleware

This paper proposes a new delivery-centric abstraction. A delivery-centric abstraction allows applications to generate content requests agnostic to location or protocol, with the additional ability to stipulate high-level requirements regarding such things as performance, security, resource consumption and monetary cost. A delivery-centric system therefore constantly adapts to fulfil these requirements, given the constraints of the environment. This abstraction has been realised through a delivery-centric middleware called Juno, which uses a reconfigurable software architecture to (i) discover multiple sources of an item of content, (ii) model each source's ability to provide the content, then (iii) adapt to interact with the source(s) that can best fulfil the application's requirements. Juno therefore utilises existing providers in a backwards compatible way, supporting immediate deployment. This paper evaluates Juno using Emulab to validate its ability to adapt to its environment

Who Watches the Watchmen: Exploring Complaints on the Web

The Web Conference 2019Under increasing scrutiny, many web companies now offer bespoke mechanisms allowing any third party to file complaints (e.g., requesting the de-listing of a URL from a search engine). While this self-regulation might be a valuable web governance tool, it places huge responsibility within the hands of these organisations that demands close examination. We present the first large-scale study of web complaints (over 1 billion URLs). We find a range of complainants, largely focused on copyright enforcement. Whereas the majority of organisations are occasional users of the complaint system, we find a number of bulk senders specialised in targeting specific types of domain. We identify a series of trends and patterns amongst both the domains and complainants. By inspecting the availability of the domains, we also observe that a sizeable portion go offline shortly after complaints are generated. This paper sheds critical light on how complaints are issued, who they pertain to and which domains go offline after complaints are issued

Common variants in the CLDN2-MORC4 and PRSS1-PRSS2 loci confer susceptibility to acute pancreatitis

BACKGROUND/OBJECTIVES: Acute pancreatitis (AP) is one of the most common gastrointestinal disorders often requiring hospitalization. Frequent aetiologies are gallstones and alcohol abuse. In contrast to chronic pancreatitis (CP) few robust genetic associations have been described. Here we analysed whether common variants in the CLDN2-MORC4 and the PRSS1-PRSS2 locus that increase recurrent AP and CP risk associate with AP. METHODS: We screened 1462 AP patients and 3999 controls with melting curve analysis for SNPs rs10273639 (PRSS1-PRSS2), rs7057398 (RIPPLY), and rs12688220 (MORC4). Calculations were performed for the overall group, aetiology, and gender sub-groups. To examine genotype-phenotype relationships we performed several meta-analyses. RESULTS: Meta-analyses of all AP patients depicted significant (p-value<0.05) associations for rs10273639 (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.81-0.97, p-value 0.01), rs7057398 (OR 1.27, 95% CI 1.07-1.5, p-value 0.005), and rs12688220 (OR 1.32, 95% CI 1.12-1.56, p-value 0.001). For the different aetiology groups a significant association was shown for rs10273639 (OR 0.76, 95% CI 0.63-0.92, p-value 0.005), rs7057398 (OR 1.43, 95% CI 1.07-1.92, p-value 0.02), and rs12688220 (OR 1.44, 95% CI 1.07-1.93, p-value 0.02) in the alcoholic sub-group only. CONCLUSIONS: The association of CP risk variants with different AP aetiologies, which is strongest in the alcoholic AP group, might implicate common pathomechanisms most likely between alcoholic AP and CP

Towards A Lightweight Incentive Scheme for Peer-to-Peer Systems

Peer-to-peer (p2p) systems rely on the contributions of peers to operate. In order to not only depend on the altruism of individual peers, a number of incentive systems have been proposed. However many of them are complex and suffer from high overhead. In this work we propose BioTrust, a lightweight incentive scheme. In contrast to other approaches, it does not require reputation histories and can operate with minimal overhead in terms of bandwidth, infrastructure, memory and computation. BioTrust is based on observations of cooperation as observed in biological systems, which show that individuals try to ally themselves with others that can best increase their own standing. Such observations are prevalent in evolutionary systems where individuals must weigh off their own individual needs against the need for cooperation to survive. Using these models, BioTrust has been developed to extract and modify some of the most useful properties of biological systems to work effectively in a p2p environment. It is shown through simulation that this scheme encourages honest peers, which leads to a close to optimal behavior in the system context as well as for single peers

Performance and Availability in Peer-to-Peer Content Distribution Systems: A Case for a Multilateral Incentive Approach

The peer-to-peer paradigm offers the potential to address many of the challenges related to large-scale content distribution over the Internet (e.g., scalability, costs, etc.). However, currently, many approaches fail to offer the quality of service supported by over-provisioned client-server distribution systems such as RapidShare and YouTube. The reason for this is that peer-to-peer systems must operate under the constraints placed on them by contributing users. Consequently, selfish, strategic, or malicious users often lower the overall system utility. To address this, incentive mechanisms are employed to motivate such users to cooperate with the system (e.g., those that contribute more, receive more in return). Many users, however, observe that popular systems such as BitTorrent (employing tit-for-tat as incentive mechanism), are often ineffective at fulfilling a set of key content distribution requirements, namely performance and availability. The overarching goal of this thesis is therefore to extend existing incentive mechanisms to better fulfil these core requirements. At first, this thesis validates and quantifies these casual observations regarding peer-to-peer performance and content availability. To achieve this we carry out two major measurement studies in the BitTorrent system, the current de-facto standard for peer-to-peer content distribution. To this end we identify widespread performance and availability problems that, through detailed analysis, are attributed to ineffective incentive design. In particular, we find that the current popular approach of ’tit-for-tat’ fails to incite sufficient cooperation amongst users to ensure high performance and content availability. Further analysis shows that this is caused by a lack of incentives for seeding (i.e., the process of remaining as a data source after one has downloaded the entire file). Based on these findings, we subsequently study a set of intuitive solutions to overcome what we call the seeder promotion problem. The purpose of this analysis is to narrow the solution space and to shape a more sophisticated incentive design. In order to achieve this, three abstract cross-torrent incentive approaches are detailed, as well as single-torrent incentive mechanisms. Each of these approaches are then quantitatively analysed through extensive trace-based simulations. These analysis further confirm our finding that bilateral incentive strategies (e.g., tit-for-tat) are insufficient at providing robust incentives for seeders. This is because most users (i) do not meet each other repeatedly and (ii) do not simultaneously require each other’s content. Instead, it is shown that the only way to overcome performance and availability issues is to use multilateral incentive strategies (i.e., to allow users to contribute to one user yet receive reciprocation from another). Finally, we design and evaluate a novel multilateral incentive mechanism, named FairSwarm.KOM. Unlike digital currency systems (in which contribution information is globally visible) or tit for-tat (where no propagation of credit points occurs), FairSwarm.KOM uses one-hop information of the overlay network to evaluate the cooperativeness of the peers. Through the use of extensive trace-based simulations, it is shown that FairSwarm.KOM improves the download performance of the popular BitTorrent system by more than 86%, while guaranteeing high levels of file availability (>99%). Most importantly, these two properties are achieved without harming the fairness of individual users and with an extremely low overhead