Words like pirates and anti-pirates are becoming common features in the cultural political debate of today, and the file-sharing phenomenon has become a more and more delicate and disputed subject. The fact that people are organizing in networks to swap computerfiles with each other has, among other things, led film and music companies from all over the world to initiate a number of anti-piracy organizations, assigned to protect the right to culture and information. The industrial organization Antipiratbyrån (the Anti-pirate Bureau) and the network Piratbyrån (the Pirate Bureau) have on several occasions been used to represent the prevailing conflict in Sweden. The purpose of this study is to apply a sociological perspective to the collective act of file sharing. Additionally, the purpose is to argue that the activity can be understood as a social movement, although it is rarely referred to as such. By focusing on the distinctly organized part of the file-sharing movement, the goal has principally been to answer how the collective action and the conveyance of knowledge, that is taking place within the movement, can be understood and which the fundamental ideas are. The study has its starting point in theories about the cognitive praxis – or core identity – of social movements. Among the methods used, interviews with representatives from Piratbyrån were valuable tools, but also other sources, like the Piratbyrån website and forum along with their participation in the media, have been the basis of the analysis. This led to a few conclusions worth considering. The most important result of the study is that it is relevant to talk about a new social movement. This movement is above all characterized by individual autonomy, expressed in a fundametal belief in the individual and some kind of “egoistic” solidarity. Closely connected to this is the everyday practice that makes the existence of the movement possible. The conclusion of the study is that the use of the technology is experienced as a political act, associated by the activists to a decentralization of power and control. Therefore, any restraint of the technology is also experienced as a restraint of man’s autonomy.

<p>Because of the slow access time of disk storage, storage management is crucial to the performance of many large scale computer systems. This thesis studies performance issues in buffer cache management and disk layout management, two important components of storage management. </p><p>The buffer cache stores popular disk pages in memory to speed up the access to them. Buffer cache management algorithms used in real systems often have many parameters that require careful hand-tuning to get good performance. A self-tuning algorithm is proposed to automatically tune the page cleaning activity in the buffer cache management algorithm by monitoring the I/O activities of the buffer cache. This algorithm achieves performance comparable to the best manually tuned system.</p><p>The global data structure used by the buffer cache management algorithm is protected by a lock. Access to this lock can cause contention which can significantly reduce system throughput in multi-processor systems. Current solutions to eliminate lock contention decrease the hit ratio of the buffer cache, which causes poor performance when the system is I/O-bound. A new approach, called the multi-region cache, is proposed. This approach eliminates lock contention, maintains the hit ratio of the buffer cache, and incurs little overhead. Moreover, this approach can be applied to most buffer cache management algorithms.</p><p>Disk layout management arranges the layout of pages on disks to improve the disk I/O efficiency. The typical disk layout approach, called Overwrite, is optimized for sequential I/Os from a single file. Interleaved writes from multiple users can significantly decrease system throughput in large scale systems using Overwrite. Although the Log-structured File System (LFS) is optimized for such workloads, its garbage collection overhead can be expensive. In modern and future disks, because of the much faster improvement of disk transfer bandwidth over disk positioning time, LFS performs much better than Overwrite in most workloads, unless the disk is close to full. A new disk layout approach, called HyLog, is proposed. HyLog achieves performance comparable to the best of existing disk layout approaches in most cases.

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Idag har vi mängder av data på våra lagringsmedia vilket gör dem till en värdefull informationskälla. Om denna data raderas betyder det inte att den är borta för alltid. Data finns fortfarande kvar på lagringsmediet och går att återskapa med så kallad file carving. Att kunna återskapa data är en viktig del inom den polisiära verksamheten, men även för andra verksamheter som förlorat data. Det finns dock vissa problem som kan ställa till med besvär när data ska återskapas. När filer inte är lagrade i sammanhängande datablock blir de fragmenterade vilket innebär problem. För att ta reda på hur stort problemet egentligen är utfördes tre test med den kommersiella programvaran EnCase och open source programvarorna Foremost, PhotoRec och Scalpel. Resultatet visade tydligt att gratisprogrammet PhotoRec var bättre än de andra programmen, men kanske mest förvånande är att det kommersiella och dyra programmet EnCase inte lyckades speciellt bra. Det framgick även att samtliga program har stora problem med att återskapa fragmenterade filer, men det var återigen gratisprogramvaran PhotoRec som presterade bäst.

“Heavy” file sharers’ and “heavy” activists’ values and attitudes toward file sharing and intellectual property rights are analyzed in this thesis, with a focus on the conflict between property owners and non-owners. The purpose of this MA thesis is to investigate the perception of file sharing and intellectual property rights on the Internet. The main research questions is: How do “heavy” file sharers and “heavy” activists perceive file sharing and intellectual property rights on the Internet?. For answering it, critical political economy and both qualitative and quantitative methods are used. Therefore, the paper consists of two major parts. In the first part, the theoretical framework is introduced. In the second part, empirical research is presented and the theoretical framework is applied to the analysis of the gathered data. Data were collected with the help of a survey. The main results of the study suggest that “heavy” file sharers and “heavy” activists tend to have left-wing values and a left-wing political agenda behind file sharing, and perceive culture, and information and knowledge as “public goods”. Furthermore, “heavy” file sharers and “heavy” activists tend to contribute to the Net gift economy and share their created content in a way that constitutes an alternative to intellectual property rights, which they see as out-of-date.

<p>Because of the slow access time of disk storage, storage management is crucial to the performance of many large scale computer systems. This thesis studies performance issues in buffer cache management and disk layout management, two important components of storage management. </p><p>The buffer cache stores popular disk pages in memory to speed up the access to them. Buffer cache management algorithms used in real systems often have many parameters that require careful hand-tuning to get good performance. A self-tuning algorithm is proposed to automatically tune the page cleaning activity in the buffer cache management algorithm by monitoring the I/O activities of the buffer cache. This algorithm achieves performance comparable to the best manually tuned system.</p><p>The global data structure used by the buffer cache management algorithm is protected by a lock. Access to this lock can cause contention which can significantly reduce system throughput in multi-processor systems. Current solutions to eliminate lock contention decrease the hit ratio of the buffer cache, which causes poor performance when the system is I/O-bound. A new approach, called the multi-region cache, is proposed. This approach eliminates lock contention, maintains the hit ratio of the buffer cache, and incurs little overhead. Moreover, this approach can be applied to most buffer cache management algorithms.</p><p>Disk layout management arranges the layout of pages on disks to improve the disk I/O efficiency. The typical disk layout approach, called Overwrite, is optimized for sequential I/Os from a single file. Interleaved writes from multiple users can significantly decrease system throughput in large scale systems using Overwrite. Although the Log-structured File System (LFS) is optimized for such workloads, its garbage collection overhead can be expensive. In modern and future disks, because of the much faster improvement of disk transfer bandwidth over disk positioning time, LFS performs much better than Overwrite in most workloads, unless the disk is close to full. A new disk layout approach, called HyLog, is proposed. HyLog achieves performance comparable to the best of existing disk layout approaches in most cases.

Downloading information from the Internet is an incredibly popular activity. Some of the information is used for scholarly or educational purposes, some is used for entertainment, as well as all sorts of other purposes. Books, movies, video games, and music are being downloaded by an increasing number of Internet users. Some of these digital files contain information that is perfectly legal to use and share but a great majority of these files are illegal to download. Recent technological developments in digital and Internet technologies have made the downloading of both legal and illegal digital content very easy and very fast. These technological developments have brought about a tension between two conflicting interests among Internet users. One of these interests drives people to download content illegally and the other interest drives people to act in ways intended to stop such illegal downloading. Much legal attention has been given to this issue in the past few years, but little sustained philosophical attention. In this thesis I discuss the moral issues that come along with the illegal downloading of information via the Internet with a focus on music files. I present the issue of illegal music downloading through the use of a scalar utilitarian theory with a focus on preference satisfaction. I conclude that the act of downloading is in aggregate morally permissible, and further, that the status quo bundle of intellectual property rights (copyright) that protect these files should be removed. Also, I provide a rough sketch of how all people concerned can satisfy both of the conflicting interests (mentioned above) through the use of copyleft protections.

With the growing of Internet, people use network frequently. Many PC applications have moved to the network-based environment, such as text processing, calendar, photo management, and even users can develop applications on the network. Google is a company providing web services. Its popular services are search engine and Gmail which attract people by short response time and lots amount of data storage. It also charges businesses to place their own advertisements. Another hot social network is Facebook which is also a popular website. It processes huge instant messages and social relationships between users. The magic power of doing this depends on the new technique, Cloud Computing. Cloud computing has ability to keep high-performance processing and short response time, and its kernel components are distributed data storage and distributed data processing. Hadoop is a famous open source to build cloud distributed file system and distributed data analysis. Hadoop is suitable for batch applications and write-once-and-read-many applications. Thus, currently there are only fewer applications, such as pattern searching and log file analysis, to be implemented over Hadoop. However, almost all database applications are still using relational databases. To port them into cloud platform, it becomes necessary to let relational database running over HDFS. So we will test the solution of FUSE-DFS which is an interface to mount HDFS into a system and is used like a local filesystem. If we can make FUSE-DFS performance satisfy user¡¦s application, then we can easier persuade people to port their application into cloud platform with least overhead.

The fast growing bandwidth has made the development of cloud storage. More and more resource has put in cloud storage. In this thesis, we proposed a new cloud storage that consists of a single main server and multiple data servers. The main server controls system-wide activities such as data server management. It also periodically communicates with each data server and collects its state. Data servers store data on local disks as Windows files. In order to response to the large number of data access, Selection of the server which is necessary to offer equalized performance. In this paper, we propose a server selection algorithm using different parameters to get the performance metrics which enables us to balance multi-resource from server-side. We design new cloud storage and implement the algorithm. According to upload experiment, the difference between the maximum and the minimum free space when using our algorithm is less than 5GB. But using the random mode, the free space difference is increased as time, and the maximum is 30GB. In the mixed experiment, we added the download mode, and our algorithm is fewer than 10GB. The result of the random mode approximated to the first experiment. Finally, our algorithm obtains 10% and 3% speedup in upload throughput by upload experiment and mixed experiment, 10% speedup in download throughput by mixed experiment.

Peer-to-peer file sharing has overturned the traditional way to communication, and has great impacts on society. But as so far, there are only few researches concerning this problem from users¡¦ point of view, why and how users take use of it is still equivocal. Therefore in this research, I examined the motivations and behavior of P2P uses with uses and gratifications approach, and further more, whether motivations for P2P uses explain users¡¦ behaviors and considered the contribution of individual characteristics are also examined. As for motivations, a factor analysis revealed five motivations to use P2P file sharing software: Information seeking, Convenience, Library storage, Interpersonal communication and Self-achievement. Motivations are related to individual characteristics, including gender, age, the duration of internet use and P2P use, income, and education. Several motivations and individual differences predict P2P use. And grouping users with cluster analysis, this research found three types of users: highly involved users, low involved users, and those who just want to download files. Highly involved users launch software frequently, have the strong motivations and are willing to share files with others. On the contrary, low involved users use less frequently, and have the relatively weak motivation of P2P use. Those who just download files are unwilling to share files with others.