This research focuses on introducing a novel concept to design a scalable, hierarchical interest-based overlay Peer-to-Peer (P2P) system. We have used Linear Diophantine Equation (LDE) as the mathematical base to realize the architecture. Note that all existing structured approaches use Distributed Hash Tables (DHT) and Secure Hash Algorithm (SHA) to realize their architectures. Use of LDE in designing P2P architecture is a completely new idea; it does not exist in the literature to the best of our knowledge. We have shown how the proposed LDE-based architecture outperforms some of the most well established existing architecture. We have proposed multiple effective data query algorithms considering different circumstances, and their time complexities are bounded by (2+ r/2) only; r is the number of distinct resources. Our alternative lookup scheme needs only constant number of overlay hops and constant number of message exchanges that can outperform DHT-based P2P systems. Moreover, in our architecture, peers are able to possess multiple distinct resources. A convincing solution to handle the problem of churn has been offered. We have shown that our presented approach performs lookup queries efficiently and consistently even in presence of churn. In addition, we have shown that our design is resilient to fault tolerance in the event of peers crashing and leaving. Furthermore, we have proposed two algorithms to response to one of the principal requests of P2P applications’ users, which is to preserve the anonymity and security of the resource requester and the responder while providing the same light-weighted data lookup.

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I en värld där kraven på flexibilitet, säkerhet och hårdvaruoptimering är nyckelfaktorer när det kommer till att välja IT-miljöer för företag blir virtuella skrivbord mer och mer poulära. Med dessa miljöer finns det också problem när det kommer till användarupplevelsen om nätverket ifråga inte kan uppfylla de krav som ett sådant system ställer. I detta arbete undersöks implikationerna vissa nätverksvariabler kan ha för en Virtual Desktop-infrastruktur, VDI. För att belysa dessa problem har två tester utförts på en VDI miljö. Det första testet gick ut på att mäta latensen då skrivbordsmiljön renderades för klienten från virtualiseringsservern vid olika nätverksdiamterar. Det andra testet gick ut på att mäta samma latens vid olika nätverksbelasting på anslutningen mellan klienten och virtualiseringsservern. När det blev tydligt att nyckelfaktorn var nätverksbelastningen skapades ett test för att undersöka klientens möjlighet till påverkan av bandbredden. Överföringen av data till användarens lokala skrivbord som i förlängningen huseras på virtualiseringsservern tog upp hela bandbredden och lämnade inget för VDI-trafiken och stänger i förlängningen ner hela VDI systemet. Detta löstes genom att implementera Quality Of Service medelst Traffic Policing . Därmed kan användarens möjlighet att nyttja bandbredden till virtualiseringsservern begränsas. / In a world where the demand for flexibility, security, and hardware optimization are key factors when it comes to implementing a corporate IT environment Virtual Desktop solutions a gaining more and more ground. With these environments there are also issues when it comes to user experience if the network in question is unable to fulfill the specifications that such an environment requires. We have looked at the implications some network variables might have for a VDI solution. To shed a light on these issues we have conducted two tests in an VDI environment. The first test consisted of measuring the latency at which the desktop on the client was rendered from the virtualization server at different network sizes. The second test was to measure the same latency at different bandwidth loads on the line between the client and the Virtualization Host. As we realised that the key factor was the bandwidth load, we made a test to measure the way a client could influence that bandwidth. We saw that by transferring data to the desktop (i.e. the Virtualization Host) one user could personally take up the whole bandwidth and leave noting for the VDI traffic, rendering it useless. This was solved by implementing Quality of Service in the form of Traffic policing, thus restricting the amount of bandwidth the user could use for file transfers.