<p>Vi, två studerande vid Karlstads universitet, har efter önskemål från IBM intervjuat tre representanter från utvalda svenska tillverkningsföretag om hur de ställer sig till Linux på klientsidan och sedan jämfört detta med vad IT-analysföretag anser om Linux och en</p><p>övergång till detta på klientsidan. Vi har även utfört en djupintervju med en anställd på IBM för att ta del av deras syn och åsikter om varför de valt att satsa på Linux på klientsidan och vägt in detta i våra intervjuer med tillverkningsföretagen.</p><p>Vi frågar oss, är det någon skillnad i uppfattning mellan hur olika IT-analysföretag ser och skriver om Linux och hur markanden ser på Linux och vad de egentligen tycker?</p><p>Att Linux kommer gå en ljus framtid till möte är samtliga involverade parter i vår uppsats eniga om. Trots detta skiljer sig deras åsikter om vilket operativsystem som är det mest kostnadseffektiva, IT-analysföretagen säger Linux, tillverkningsföretagen säger Microsoft. En ökad konkurrens på marknaden ser samtliga som positivt men poängterar att det måste finnas ett verkligt skäl till en övergång då det kostar mycket pengar och att det är så pass mycket att tänka på.</p>

Modern smartphones integrate ubiquitous access to voice, data, and email communication and allow users to rapidly handle both personal and corporate business affairs. This is possible because of the smartphone’s constant connectivity with the Internet. Digital forensic investigators have long understood the value of smartphones as forensic evidence, and this thesis seeks to provide new tools to increase the amount of evidence that one can obtain and analyze from an Android smartphone. Specifically, by using proven data carving algorithms we try to uncover information about the phone’s connection to wireless access points in a capture of the device’s volatile memory.

A crescente oferta de programas de código aberto na rede mundial de computadores expõe potenciais usuários a muitas possibilidades de escolha. Em face da pluralidade de interesses desses indivíduos, mecanismos eficientes que os aproximem daquilo que buscam trazem benefícios para eles próprios, assim como para os desenvolvedores dos programas. Este trabalho apresenta o AppRecommender, um recomendador de aplicativos GNU/Linux que realiza uma filtragem no conjunto de programas disponíveis e oferece sugestões individualizadas para os usuários. Tal feito é alcançado por meio da análise de perfis e descoberta de padrões de comportamento na população estudada, de sorte que apenas os aplicativos considerados mais suscetíveis a aceitação sejam oferecidos aos usuários. / The increasing availability of open source software on the World Wide Web exposes potential users to a wide range of choices. Given the individuals plurality of interests, mechanisms that get them close to what they are looking for would benefit users and software developers. This work presents AppRecommender, a recommender system for GNU/Linux applications which performs a filtering on the set of available software and individually offers suggestions to users. This is achieved by analyzing profiles and discovering patterns of behavior of the studied population, in a way that only those applications considered most prone to acceptance are presented to users.

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores - Major de Telecomunicações. Faculdade de Engenharia. Universidade do Porto. 2008

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores - Major em Telecomunicações. Faculdade de Engenharia. Universidade do Porto. 2008

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores (Major de Telecomunicações). Faculdade de Engenharia. Universidade do Porto. 2009

[Abstract]: This is a project to implement a Mice and Elephants queueing discipline, which favoursshort flows over long flows, on Linux. The project has three aims. The first aim is toproduce a prototype Mice and Elephants router for the purpose of further evaluation ofthe Mice and Elephants strategy and the Shortest Job First strategy. The second aim is tomake a contribution to Linux by making my implementation as code that is both fit fordistribution with Linux and useful in a small business or domestic setting. The third aimis to explore and document a method of creating Linux queueing disciplines in general.

<p>Streaming video and VoIP are two popular services used over the Internet, and as the number of users increases, the demand on the network routers also increases. Since both streaming video and VoIP have a variable traffic flow, the routers must always have some free space in their receive buffers to handle traffic bursts. If not, packet loss may occur that will result in a degraded quality of the services. In this project, a fuzzy logic based Active Queue Management (AQM) will be implemented, which might help reduce this problem. This algorithm has currently only been tested in a simulated environment. This algorithm will then be evaluated and compared to some of the existing AQMs. The results will also be compared to a stream that only uses a First-In, First-Out (FIFO) queue, which will work as a baseline. Since an AQM is not the only means used to reduce delay and jitter, different AQMs will also be combined with two different transport protocols, User Datagram Protocol (UDP) and the new Datagram Congestion Control Protocol (DCCP). The resulting implementation performed on a par with RED (Random Early Detection), one of the most common AQMs.</p>

No description available.

Device driver is an important part of an operating system. All I/O device accesses must be done through device drivers. Because they reside in the kernel address space, a driver fault may lead to a system failure, which is not acceptable for embedded systems with high dependability requirements. Many embedded systems execute safety-critical tasks and hence a system failure will cause a great loss. Running drivers in user mode can prevent the drivers from damaging the operating system kernel. User mode driver resulted in a large performance degradation when it was proposed during the 1980s. Nonetheless, the performance has been improved due to good implementations of system call and context switch. According to the previous study, the performance of a user mode driver for a Gigabit network card can achieve 93% of that of the kernel mode driver in a Linux-based platform. Although the performance of user mode drivers has been improved, there is still a crucial problem which handicaps user mode drivers from being utilized widely. That is, drivers have to be modified in order to support a given user mode driver framework. In this thesis, we propose a user mode driver framework, which allows a kernel mode driver to be executed in the user space without any code modifications. The framework emulates the kernel-space execution environment in the user space, In this framework, communication between user mode driver process and the kernel is done through I/O request redirection and shared memory. We implemented the framework on an ARM Linux based embedded system platform. The prototype of our framework supports two classes of user mode drivers: character device drivers and network interface drivers. The former includes a LED and a 7-segment user mode device drivers, and the latter consists of an Ethernet user mode device driver. Our work has two contributions. First of all, we enable direct execution of kernel mode drivers in the user space without any driver code modifications.. Second, we evaluate the performance of user mode drivers in an embedded system. To the best of our knowledge, no results about performance of user mode drivers on embedded systems have been reported. According to the experimental results, the performance of our user mode drivers can achieve 61%~99% of that of the kernel mode ones. This demonstrates that the framework we propose can improve the reliability of system under the acceptable costs of performance.