<p>The computer engineering group at Linköping University has parts of their research dedicated to networks-on-chip and components used in network components and terminals. This research has among others resulted in the SoCBUS NOC and a flow based network protocol processor. The main objective of this project was to integrate these components into an IP router with two or more Gigabit Ethernet interfaces.</p><p>A working system has been designed and found working. It consists of three main components, the input module, the output module and a packet buffer. Due to the time constraint and the size of the project the packet buffer could not be designed to be as efficient as possible, thus reducing the overall performance. The SoCBUS also has negative impact on performance, although this could probably be reduced with a revised system design. If such a project is carried out it could use the input and output modules from this project, which connect to SoCBUS and can easily be integrated with other packet buffers and system designs.</p>

<p>Voice over IP technology (VoIP) has recently gained popularity among consumers. Many popular VoIP services exist only as software for PCs. The need of taking such services out of the PC, into a stand-alone device has been discovered, and this thesis work deals with the development of such a device. The thesis work is done for Häger Scandinavia AB, a Swedish telephone manufacturer. This thesis work covers the design of a complete prototype of a table-top VoIP telephone running an embedded Linux Operating system. Design areas include product development, hardware design and software design.The result is a working prototype with hardware and corresponding Linux device drivers. The prototype can host a Linux application adapted to it. Conclusions are that the first hardware version has worked well and that using an open-source operating system is very useful. Further work consists of implementing a complete telephony software application in the system, evaluation of system requirements and adapting the prototype for a commercial design.</p>

The development of web technology has led to the emergence of web aggregation, a service that collects existing web data and turns them into more useful information. We review the development of both comparison and relationship aggregation and discuss their impacts on various stakeholders. The aggregator’s capability of transparently extracting web data has raised challenging issues in database and privacy protection. Consequently, new regulations are introduced or being proposed. We analyze the interactions between aggregation and related policies and provide our insights about the implications of new policies on the development of web aggregation. / Singapore-MIT Alliance (SMA)

In this thesis, we exercised the componentization technique to componentize the Netfilter architecture in Linux network system. Netfilter is a software architecture for filtering packets. System administrator can register packet-matching rules and target handling function into the system. Netfilter matches packets according to the rules and processes them by the corresponding target functions. By componentizing the architecture, we can improve the elasticity and the reusability of Netfilter. Hot-swapping is an important procedure in componentized software system. In this study, we implemented hot-swapping based on the work developed by Fan[1]. It stores the relocation information of exporting symbols into the module symbol table. With this information, we are able to dynamically change the caller-callee relationship of modular components at run time. In addition, we extend their work to allow the same modular component to be loaded into Linux kernel for more than once so that the same component can be replicated in the system. We started with decomposing all the ¡§hook¡¨ functions into smaller and simpler components and then for each component, we added in-ports and out-ports and registered its own iptables, and we fixed the limitation of only one instance of a module allowed in kernel and broke the hard rule in iptables. As a result, after Netfilter componentization, we are able to illustrate new configurations that cannot be done in the original architecture, and the system becomes further compact with only necessary components loaded in the system. This reflects in slight performance improvement in our experiments, which is not usually seen in other frameworks due to componentization overhead.

Currently, a viable solution to provide multicast provision over a multiprotocol label switch with traffic engineering (MPLS-TE) domain is unavailable because of the missing link able to couple multicast traffic distribution with an MPLS-TE enabled network. This is due to the limited or less research investigation that was done in this area. Most of the investigation methods tackle the problem individually such as deploying internet protocol (IP) multicast in a plain network or MPLS domain but without considering a combination of both technologies that is aware of differentiated services requirements. This thesis presents an alternative solution for the multicast differentiated services provision problem over a MPLS-TE enabled network. The approach is exposed and analyzed through a practical solution that was developed within a network simulation environment. The research presented in this thesis orchestrates the already available technologies offered by the multicast protocols suite and differentiated services (DiffServ) aware MPLS-TE that allows applying separately the constraint-based routing and admission control to different classes of services. The novelty and solution of this thesis relies on using MPLS constraint-based routing concepts (e.g.traffic trunks) in order to solve TE issues revealed during multicast traffic distribution.

Border Gateway Protocol (BGP) is the backbone of routing infrastructure in the Internet. In its current form, it is an insecure protocol with potential for propagation of bogus routing information. There have been several high-profiles Internet outages linked to BGP in recent times. Several BGP security proposals have been presented in the literature; however, none has been adopted so far and, as a result, securing BGP remains an unsolved problem to this day. Among existing BGP security proposals, Secure BGP (S-BGP) is considered most comprehensive. However, it presents significant challenges in terms of number of signature verifications and deployment considerations. For it to provide comprehensive security guarantees, it requires that all Autonomous Systems (ASes) in the Internet to adopt the scheme and participate in signature additions and verifications in BGP messages. Among others, these challenges have prevented S-BGP from being deployed today. In this thesis, we present two novel lightweight security protocols, called Credible BGP (C-BGP) and Hybrid Cryptosystem BGP (HC-BGP), which rely on security mechanisms in S-BGP but are designed to address signature verification overhead and deployment challenges associated with S-BGP. We develop original and detailed analytical and simulation models to study performance of our proposals and demonstrate that the proposed schemes promise significant savings in terms of computational overhead and security performance in presence of malicious ASes in the network. We also study the impact of IP prefix hijacking on control plane as well as data plane. Specifically, we analyze the impact of bogus routing information on Inter-Domain Packet Filters and propose novel and simple extensions to existing BGP route selection algorithm to combat bogus routing information.

Currently, a viable solution to provide multicast provision over a multiprotocol label switch with traffic engineering (MPLS-TE) domain is unavailable because of the missing link able to couple multicast traffic distribution with an MPLS-TE enabled network. This is due to the limited or less research investigation that was done in this area. Most of the investigation methods tackle the problem individually such as deploying internet protocol (IP) multicast in a plain network or MPLS domain but without considering a combination of both technologies that is aware of differentiated services requirements. This thesis presents an alternative solution for the multicast differentiated services provision problem over a MPLS-TE enabled network. The approach is exposed and analyzed through a practical solution that was developed within a network simulation environment. The research presented in this thesis orchestrates the already available technologies offered by the multicast protocols suite and differentiated services (DiffServ) aware MPLS-TE that allows applying separately the constraint-based routing and admission control to different classes of services. The novelty and solution of this thesis relies on using MPLS constraint-based routing concepts (e.g.traffic trunks) in order to solve TE issues revealed during multicast traffic distribution.

Network monitoring has become a necessity to aid in the management and operation of large networks. Passive network monitoring consists of extracting metrics (or any information of interest) by analyzing the traffic that traverses one or more network links. Extracting information from a high-speed network link is challenging, given the great data volumes and short packet inter-arrival times. These difficulties can be alleviated by using extremely efficient algorithms or by sampling the incoming traffic. This work improves the state of the art in both these approaches. For one-way packet delay measurement, we propose a series of improvements over a recently appeared technique called Lossy Difference Aggregator. A main limitation of this technique is that it does not provide per-flow measurements. We propose a data structure called Lossy Difference Sketch that is capable of providing such per-flow delay measurements, and, unlike recent related works, does not rely on any model of packet delays. In the problem of collecting measurements under the sliding window model, we focus on the estimation of the number of active flows and in traffic filtering. Using a common approach, we propose one algorithm for each problem that obtains great accuracy with significant resource savings. In the traffic sampling area, the selection of the sampling rate is a crucial aspect. The most sensible approach involves dynamically adjusting sampling rates according to network traffic conditions, which is known as adaptive sampling. We propose an algorithm called Cuckoo Sampling that can operate with a fixed memory budget and perform adaptive flow-wise packet sampling. It is based on a very simple data structure and is computationally extremely lightweight. The techniques presented in this work are thoroughly evaluated through a combination of theoretical and experimental analysis.

This thesis work focuses on designing a survivable IP-core network with the minimal investment of spare capacity. A span-oriented spare capacity allocation (SCA) scheme is proposed to satisfy customers' availability requirements in the end-to-end (E2E) sense. The novelty of the proposed SCA scheme is that it meets the E2E availability requirements despite the lack of knowledge of E2E bandwidth by employing protection rings covering all links in the network. Different ring selection methods are presented and also compared from the aspect of network redundancy and LP feasibility which provide more flexibility to the design. The proposed SCA algorithm further minimizes total cost of spare capacity by incorporating partial protection within the proposed architecture. The simulation results show that it can significantly reduce the spare capacity consumption depending on the availability. The proposed SCA scheme also performs better in terms of redundancy than that of two other dominant methods available these days.

Detta examensarbete behandlar problemet med att testa inbyggda system i kontorsmiljö. För att göra detta och därigenom kunna göra anrop på det inbyggda systemets API, måste detta anrop skickas som ett seriellt datapaket över en seriell kommunikationslänk som TCP/IP. Detta möjliggjordes genom att först upprätta en kommunikationslänk med protokollet TCP/IP, där användningen av POSIX-sockets tillämpades. För att packa ner och packa upp funktionsanropen till seriell data implementerades ett protokoll som följdes när detta utfördes. Hantering av data i samband med överföring över TCP/IP sköttes av ett protokoll vid namn BGSFP, ett protokoll som bygger på det tidigare protokollet TSFP.