Global System for Mobile Communications (GSM) networks are receiving increasing attention in the open-source community. Open-source software allows for deployment of a mobile cellular network with lower costs, more customization, and scalable control. Two popular projects have emerged that offer varying network architectures and allow users to implement a GSM network in different capacities depending on individual needs. Osmocom provides more network control and scalability but requires commercial Base Transceiver Station (BTS) hardware with limited availability and closed source code. OpenBTS provides minimal GSM network functionality with more easily available and open-source hardware; however, it does not allow multi-cellular network configuration. This thesis offers a significant contribution towards a fully open-source GSM network by integrating the two major open-source communities, Osmocom and OpenBTS. Specifically, the Osmo-USRP program provides an inter-layer interface between the different network architectures of two GSM base station projects. Inter-layer primitive messages are processed in a thread multiplexer that manages logical channels across the interface. Downstream flow control is implemented in order to receive data frames on time for transmitting at the appropriate GSM frame number (FN). Uplink measurements, which are necessary for decision making in the Base Station Controller (BSC), are also gathered in the physical layer of Osmo-USRP and reported to Osmocom. Osmo-USRP operation is tested using a Universal Software Radio Peripheral (USRP), a relatively inexpensive and accessible Software-Defined Radio (SDR). Standard GSM events are investigated for single cell and multi-cellular network configurations. These tests include subscriber authentication and encryption, location updating, International Mobile Subscriber Identity (IMSI) attach and detach, Short Message Service (SMS) storage and delivery, voice calls with the full-rate audio codec, and uplink and downlink measurement reporting. While most functionality is successfully tested, inter-cell handover is not currently implemented. Further details on the proposed implementation of program limitations, especially inter-cell handover, are also discussed. / Master of Science

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: This thesis discusses the steps that should be taken when conceptualising, designing and implementing a South African national research and education network. It looks at all aspects of specifying transmission mediums and technology, choosing hardware and interfaces and detailing node layout and optic fibre network architecture. It examines the design of a national transport backbone, as well as a metropolitan optic fibre network. It considers ways in which the network may be made future-proof, both in terms of capacity and technology, and suggests ways to integrate the incumbent tertiary and education network into a fully-fledged, world-class network. Finally it benchmarks the network against similar networks in other countries, most notably the United States of America. / AFRIKAANSE OPSOMMING: Hierdie tesis bespreek die stappe wat geneem behoort te word wanneer 'n Suid Afrikaanse nasionale navorsings en tersiêre opvoedings netwerk gekonseptualiseer, ontwerp en geïmplementeer word. Dit beskou al die aspekte rondom die spesifiseering van transmissie mediums en -tegnologie, die keuse van hardeware en koppelvlakke en die detailering van nodus uitlegte en optiese vesel netwerk argitektuur. Dit ondersoek die ontwerp van 'n nasionale transmissie ruggraat netwerk, sowel as 'n metropolitaanse optiese vesel netwerk. Dit oorweeg maniere waarmee 'n netwerk toekomsproef gemaak kan word, beide in terme van kapasiteit sowel as tegnologie, en stel maniere voor waarmee die huidige tersiêre opvoeding en navorsingsnetwerk geïntegreer kan word na 'n volwaardige, wêreldklas netwerk. Uiteindelik word die netwerk ontwerp vergelyk met soortgelyke netwerke in ander lande, spesifiek in die Verenigde State van Amerika.

The aim of this thesis project to design and implement a campus network based on IPv6, as IPv6 is the protocol of the future communication.There are many papers available which discuss upgrade from IPv4 to IPv6 and their side by side implementations and functionalities. Contrary to this we are working on running a network entirely based on IPv6. So we built this network infrastructure, monitored it and tested it.A network working on IPv6 is not just about a different addressing plan. Rather there are some serious questions. Network administrators are quite happy and comfortable with the current setup of IPv4. Would this IPv6 be able to provide them same facilities on one-to-one basis? If not, would it be upgrade or degrade on some functionality? Is there solution to every problem available or they would have to discover it themselves? All these and many more questions were faced and tackled in the course of this thesis.

The objective of this master’s thesis is monitoring and management of computer networks via SNMP protocol and its practical application. The main part describes working with SNMPc program in an experimental network through implementation of its parts into the network and configuration of SNMP agents on routers, switch and end station. This thesis includes the results of traffic testing, disconnected links, effects of traffic load on QoS parameters, making longterm statistics, baselines and alarms. The thesis also includes parametres obtained with SNMP protocol from network nodes and end station.

Cette thèse considère les réseaux de capteurs sans fil (RCSF) de grande dimension (de l'ordre du million de noeuds). Les questions posées sont les suivantes : comment prédire le bon fonctionnement et calculer avant déploiement les performances d'un tel réseau, sachant qu'aucun simulateur ne peut simuler un réseau de plus de 100 000 noeuds ? Comment assurer sa configuration pour garantir performance, passage à l'échelle, robustesse et durabilité ? La solution proposée dans cette thèse s'appuie sur une architecture de RCSF hétérogène à deux niveaux, dont le niveau inférieur est composé de capteurs et le niveau supérieur de collecteurs. La première contribution est un algorithme d'auto-organisation multi-canal qui permet de partitionner le réseau inférieur en plusieurs sous-réseaux disjoints avec un collecteur et un canal de fréquence par sous-réseau tout en respectant le principe de réutilisation de fréquence. La seconde contribution est l'optimisation du déploiement des collecteurs car leur nombre représente celui des sous-réseaux. Les problèmes traités ont été : l'optimisation des emplacements des puits pour un nombre prédéfini de puits et la minimisation du nombre de puits ou du coût pour un nombre prédéfini de sauts dans les sous-réseaux. Une solution intuitive et appropriée pour assurer à la fois performances réseaux et coût, est de partitionner le réseau inférieur en sous-réseaux équilibrés en nombre de sauts. Pour ce faire, la topologie physique des puits est une répartition géographique régulière en grille (carrée, triangulaire, etc.). Des études théoriques et expérimentales par simulation des modèles de topologie montrent, en fonction des besoins applicatifs et physiques, la méthodologie de choix et le calcul des meilleures solutions de déploiement. / This thesis considers the large-scale wireless sensor network (LSWSN) consisting of million nodes. The questions are: how to predict the good working and to compute before deployment the performances of such a network, knowing that no simulator can simulate a network of more than 100000 nodes? How to ensure its configuration to ensure performance, scalability, robustness and longevity? The solution proposed in this thesis is based on a two-tiered heterogeneous architecture of WSN in which the level 1 is composed of sensors and the level 2 of collectors. The first contribution is a multi-channel self-organization algorithm, which allows partitioning the network of level 1 into several disjointed sub-networks with one collector and one frequency channel while respecting the principle of frequency reuse. The second contribution is to optimize the deployment of collectors because their number represents that of sub-networks. The problems addressed were: the optimization of sinks locations for a predetermined number of sinks, and the minimization of financial cost related of the sinks? number, for a predetermined number of hops in the sub-networks. An intuitive and appropriate solution to ensure both network performance and cost is to partition the network of level 1 into balanced sub-networks in number of hops. To do this, the physical topology of sinks is a regular geographical grid (square, triangular, etc.). Theoretical studies and simulation of topology models show, depending on application requirements (node density, charge application, etc.) and physical (radio range, surveillance zone), the methodology of choice and the computation of the best deployment solutions.

A Internet foi projetada em contexto distante da realidade atual. Novas aplicações, novas tecnologias e dispositivos definem um novo conjunto de requisitos, que, entre outros, consiste de suporte a mobilidade, segurança, QoS e multicast. Pesquisadores de todo o mundo estão engajados no projeto da Internet do Futuro. Enquanto muitos procuram evoluir a Internet atual, outros partem do princípio de que arquitetura atual deve ser ignorada afim de se conceber uma nova arquitetura. Partindo de uma visão disruptiva, este trabalho tem por objetivo definir, projetar e avaliar experimentalmente uma forma de encaminhamento onde o multicast seja um requisito central para as aplicações. Essa forma de encaminhamento é baseada em novas relações entre entidades que se comunicam e na utilização de uma identificação/endereçamento única, não ambígua e independente da topologia: seu Título. A arquitetura Entity Title Architecture (ETArch), construída sobre uma infraestrutura baseada em redes definidas por software, estabelece novas relações entre as entidades de sistemas distribuídos. A definição do Workspace, implementado neste trabalho, permite estabelecer um canal por onde múltiplas entidades se comunicam naturalmente de uma forma multicast, permitindo ainda a mobilidade dessas entidades ao longo da rede. Identificado por seu Título, o Workspace é o destino das primitivas durante a comunicação. À medida que novas entidades se ligam ou desligam, há reconfiguração do Workspace. A abordagem definida, implementada e verificada neste trabalho representa uma forma mais eficiente de comunicação se comparada aos endereços no âmbito da camada de rede (IP Multicast) ou de aplicação (Application Layer Multicast). A arquitetura ETArch leva em conta não somente os aspectos de multicast e mobilidade das entidades, como também foi construída com a visão de incorporar em um momento futuro requisitos de QoS e segurança, sendo, portanto, um ponto de convergência para o diálogo com outros grupos de pesquisa, afim de colaborar na construção da próxima geração das redes de computadores. / Internet was designed in a totally different context, far from what we have today. New applications, new technologies and devices define a new set of requirements, which among others, is to support mobility, security, QoS and multicast. Researchers around the world are engaged in the design of the Future Internet. While many seek to evolve the current Internet, others assume that current architecture should be ignored in order to design a new architecture. From a disruptive vision, this work aims to define, design and experimentally validate a form of referral where multicast be a central requirement for applications. This form of routing is based on new relationships between entities that communicate and use of an identification/addressing based on a topology independent name that unambiguously identifies an entity: its Title. The Entity Title Architecture (ETArch), built on an infrastructure based on software defined networking, establishes new relationships between entities in distributed systems. The definition of the Workspace, implemented in this work, allows establishing a channel through which multiple entities communicate naturally by using a multicast approach, while still allowing mobility of these entities over network. Identified by its title, the Workspace is the destination of the primitives during communication. As new entities attach or detach the Workspace is reconfigured. The approach defined, implemented and varied in this work is a more efficient way of communication compared to the addressing within the network layer (IP Multicast) or application (Application Layer Multicast). ETArch takes into account not only the aspects of multicast and mobility of the entities , but also was built with the vision to incorporate into a future time QoS and security , so it is a focal point for dialogue with other research groups to collaborate in building the next generation of computer networks.

A Internet foi projetada em contexto distante da realidade atual. Novas aplicações, novas tecnologias e dispositivos definem um novo conjunto de requisitos, que, entre outros, consiste de suporte a mobilidade, segurança, QoS e multicast. Pesquisadores de todo o mundo estão engajados no projeto da Internet do Futuro. Enquanto muitos procuram evoluir a Internet atual, outros partem do princípio de que arquitetura atual deve ser ignorada afim de se conceber uma nova arquitetura. Partindo de uma visão disruptiva, este trabalho tem por objetivo definir, projetar e avaliar experimentalmente uma forma de encaminhamento onde o multicast seja um requisito central para as aplicações. Essa forma de encaminhamento é baseada em novas relações entre entidades que se comunicam e na utilização de uma identificação/endereçamento única, não ambígua e independente da topologia: seu Título. A arquitetura Entity Title Architecture (ETArch), construída sobre uma infraestrutura baseada em redes definidas por software, estabelece novas relações entre as entidades de sistemas distribuídos. A definição do Workspace, implementado neste trabalho, permite estabelecer um canal por onde múltiplas entidades se comunicam naturalmente de uma forma multicast, permitindo ainda a mobilidade dessas entidades ao longo da rede. Identificado por seu Título, o Workspace é o destino das primitivas durante a comunicação. À medida que novas entidades se ligam ou desligam, há reconfiguração do Workspace. A abordagem definida, implementada e verificada neste trabalho representa uma forma mais eficiente de comunicação se comparada aos endereços no âmbito da camada de rede (IP Multicast) ou de aplicação (Application Layer Multicast). A arquitetura ETArch leva em conta não somente os aspectos de multicast e mobilidade das entidades, como também foi construída com a visão de incorporar em um momento futuro requisitos de QoS e segurança, sendo, portanto, um ponto de convergência para o diálogo com outros grupos de pesquisa, afim de colaborar na construção da próxima geração das redes de computadores. / Internet was designed in a totally different context, far from what we have today. New applications, new technologies and devices define a new set of requirements, which among others, is to support mobility, security, QoS and multicast. Researchers around the world are engaged in the design of the Future Internet. While many seek to evolve the current Internet, others assume that current architecture should be ignored in order to design a new architecture. From a disruptive vision, this work aims to define, design and experimentally validate a form of referral where multicast be a central requirement for applications. This form of routing is based on new relationships between entities that communicate and use of an identification/addressing based on a topology independent name that unambiguously identifies an entity: its Title. The Entity Title Architecture (ETArch), built on an infrastructure based on software defined networking, establishes new relationships between entities in distributed systems. The definition of the Workspace, implemented in this work, allows establishing a channel through which multiple entities communicate naturally by using a multicast approach, while still allowing mobility of these entities over network. Identified by its title, the Workspace is the destination of the primitives during communication. As new entities attach or detach the Workspace is reconfigured. The approach defined, implemented and varied in this work is a more efficient way of communication compared to the addressing within the network layer (IP Multicast) or application (Application Layer Multicast). ETArch takes into account not only the aspects of multicast and mobility of the entities , but also was built with the vision to incorporate into a future time QoS and security , so it is a focal point for dialogue with other research groups to collaborate in building the next generation of computer networks.

La ràpida evolució d’Internet i l’àmplia gamma de noves aplicacions (per exemple, multimèdia, videoconferència, jocs en línia, etc.) ha fomentat canvis revolucionaris en la manera com ens comuniquem. A més, algunes d’aquestes aplicacions demanden grans quantitats de recursos d’ample de banda amb diversos requeriments de qualitat de servei (QoS). El desenvolupament de la multiplexació per divisió de longitud d’ona (WDM) en els anys noranta va fer molt rendible la disponibilitat d’ample de banda. Avui dia, les tecnologies de commutació òptica de circuits són predominants en el nucli de la xarxa, les quals permeten la configuració de canals (lightpaths) a través de la xarxa. No obstant això, la granularitat d’aquests canals ocupa tota la longitud d’ona, el que fa que siguin ineficients per a proveir canals de menor ample de banda (sub-longitud d’ona). Segons la comunitat científica, és necessari augmentar la transparència dels protocols, així com millorar l’aprovisionament d’ample de banda de forma dinàmica. Per tal de fer això realitat, és necessari desenvolupar noves arquitectures. La commutació òptica de ràfegues i de paquets (OBS/OPS), són dues de les tecnologies proposades. Aquesta tesi contribueix amb tres arquitectures de xarxa destinades a millorar el transport de dades sub-longitud d’ona. En primer lloc, aprofundim en la naturalesa sense connexió en OBS. En aquest cas, la xarxa incrementa el seu dinamisme a causa de les transmissions a ràfega. A més, les col·lisions entre ràfegues degraden el rendiment de la xarxa fins i tot a càrregues molt baixes. Per fer front a aquestes col·lisions, es proposa un esquema de resolució de col·lisions pro actiu basat en un algorisme d’encaminament i assignació de longitud d’ona (RWA) que balanceja de forma automàtica i distribuïda la càrrega en la xarxa. En aquest protocol, el RWA i la transmissió de ràfegues es basen en l’explotació i exploració de regles de commutació que incorporen informació sobre contencions i encaminament. Per donar suport a aquesta arquitectura, s’utilitzen dos tipus de paquets de control per a l’encaminament de les ràfegues i l’actualització de les regles de commutació, respectivament. Per analitzar els beneficis del nou algorisme, s’utilitzen quatre topologies de xarxa diferents. Els resultats indiquen que el mètode proposat millora en diferents marges la resta d’algorismes RWA en funció de la topologia i sense penalitzar altres paràmetres com el retard extrem a extrem. La segona contribució proposa una arquitectura híbrida sense i orientada a connexió sobre la base d’un protocol de control d’accés al medi (MAC) per a xarxes OBS (DAOBS). El MAC ofereix dos mètodes d’accés: arbitratge de cua (QA) per a la transmissió de ràfegues sense connexió, i pre-arbitratge (PA) per serveis TDM orientats a connexió. Aquesta arquitectura permet una àmplia gamma d’aplicacions sensibles al retard i al bloqueig. Els resultats avaluats a través de simulacions mostren que en l’accés QA, les ràfegues de més alta prioritat tenen garantides zero pèrdues i latències d’accés molt baixes. Pel que fa a l’accés PA, es reporta que la duplicació de la càrrega TDM augmenta en més d’un ordre la probabilitat de bloqueig, però sense afectar en la mateixa mesura les ràfegues sense connexió. En aquest capítol també es tracten dos dels problemes relacionats amb l’arquitectura DAOBS i el seu funcionament. En primer lloc, es proposa un model matemàtic per aproximar el retard d’accés inferior i superior com a conseqüència de l’accés QA. En segon lloc, es formula matemàticament la generació i optimització de les topologies virtuals que suporten el protocol per a l’escenari amb tràfic estàtic. Finalment, l’última contribució explora els beneficis d’una arquitectura de xarxa òptica per temps compartit (TSON) basada en elements de càlcul de camins (PCE) centralitzats per tal d’evitar col·lisions en la xarxa. Aquesta arquitectura permet garantir l’aprovisionament orientat a connexió de canals sub-longitud d’ona. En aquest capítol proposem i simulem tres arquitectures GMPLS/PCE/TSON. A causa del enfocament centralitzat, el rendiment de la xarxa depèn en gran mesura de l’assignació i aprovisionament de les connexions. Amb aquesta finalitat, es proposen diferents algorismes d’assignació de ranures temporals i es comparen amb les corresponents formulacions de programació lineal (ILP) per al cas estàtic. Per al cas de tràfic dinàmic, proposem i avaluem mitjançant simulació diferents heurístiques. Els resultats mostren els beneficis de proporcionar flexibilitat en els dominis temporal i freqüencial a l’hora d’assignar les ranures temporals. / The rapid evolving Internet and the broad range of new data applications (e.g., multimedia, video-conference, online gaming, etc.) is fostering revolutionary changes in the way we communicate. In addition, some of these applications demand for unprecedented amounts of bandwidth resources with diverse quality of service (QoS). The development of wavelength division multiplexing (WDM) in the 90's made very cost-effective the availability of bandwidth. Nowadays, optical circuit switching technologies are predominant in the core enabling the set up of lightpaths across the network. However, full-wavelength lightpath granularity is too coarse, which results to be inefficient for provisioning sub-wavelength channels. As remarked by the research community, an open issue in optical networking is increasing the protocol transparency as well as provisioning true dynamic bandwidth allocation at the network level. To this end, new architectures are required. Optical burst/packet switching (OBS/OPS) are two such proposed technologies under investigation. This thesis contributes with three network architectures which aim at improving the sub-wavelength data transport from different perspectives. First, we gain insight into the connectionless nature of OBS. Here, the network dynamics are increased due to the short-lived burst transmissions. Moreover, burst contentions degrade the performance even at very low loads. To cope with them, we propose a proactive resolution scheme by means of a distributed auto load-balancing routing and wavelength assignment (RWA) algorithm for wavelength-continuity constraint networks. In this protocol, the RWA and burst forwarding is based on the exploitation and exploration of switching rule concentration values that incorporate contention and forwarding desirability information. To support such architecture, forward and backward control packets are used in the burst forwarding and updating rules, respectively. In order to analyze the benefits of the new algorithm, four different network topologies are used. Results indicate that the proposed method outperforms the rest of tested RWA algorithms at various margins depending on the topology without penalizing other parameters such as end-to-end delay. The second contribution proposes a hybrid connectionless and connection-oriented architecture based on a medium access control (MAC) protocol for OBS networks (DAOBS). The MAC provides two main access mechanisms: queue arbitrated (QA) for connectionless bursts and pre-arbitrated (PA) for TDM connection-oriented services. Such an architecture allows for a broad range of delay-sensitive applications or guaranteed services. Results evaluated through simulations show that in the QA access mode highest priority bursts are guaranteed zero losses and very low access latencies. Regarding the PA mode, we report that doubling the offered TDM traffic load increases in more than one order their connection blocking, slightly affecting the blocking of other connectionless bursts. In this chapter, we also tackle two of the issues related with the DAOBS architecture and its operation. Firstly, we model mathematically the lower and upper approximations of the access delay as a consequence of the connectionless queue arbitrated access. Secondly, we formulate the generation of the virtual light-tree overlay topology for the static traffic case.

In 21st century, the development strategy and the management policy of Information Communication Technology (ICT) is a key issue to a nation¡¦s competitiveness. Particularly, the development of telecommunication liberalization, governance in the telecommunications regime and the relevant science and technology policies of the telecommunication industry is the most important factor for creating a leading knowledge-based economy for Information Communication Technology related industries. Looking forward to the future, the trends and developments of the convergence of telecommunication, broadcasting and internet services will drive the demand for the telecommunication and broadcasting industries to look for cost-efficient provisioning of converged multimedia services. The emerging technology of next generation network (NGN) infrastructure enables the convergence of multi-access networks to deliver the multimedia contents and application services seamlessly. Therefore, the consumers, government, and industry can obtain the benefits because of technology development and industrial cooperation. In addition, the converged broadcasting and telecommunication services as well as Fixed-Mobile Converged applications over the internets results in the needs for the improvement in network interconnectivity and service interoperability. No matter it is telecommunication, broadcasting or information, to converge as common info-communication services, such as telephony, data and multimedia will eventually run over the all IP networks. Therefore, IP Multimedia Subsystem (IMS) becomes one of the promising technologies to drive it happen. However, existing policy and regulations must cope with the changes of this development. The liberalization of broadband and communication market allows the participation of the private companies to create new investment and revenue. This research studies the possible evolution of an IP-based communication infrastructure from today's networks toward a converged next generation network and proposes an Inter-Exchange Center of Converged Network Architecture (IEXCNA), applying to VoIP service. The IEXCNA model shows more efficient in the transmission, interconnectivity and reducing implementation cost of network infrastructure. Thus the consumers are able to enjoy better quality of service and cheaper rate of use for multimedia services.

Traditional routing protocols select paths based on static link weights and converge to new paths only when there is an outright reachability failure (such as a link or router failure). This design allows routing scale to hundreds of thousands of nodes, but it comes at the cost of functionality: routing provides only simple, single path connectivity. Networked applications in the wide-area, enterprise, and data center can all benefit from network protocols that allow traffic to be sent over multiple routes en route to a destination. This ability, also called multipath routing, has other significant benefits over single-path routing, such as more efficiently using network resources and recovering more quickly from network disruptions. This dissertation explores the design of an architecture for path selection in the network and proposes a "narrow waist" interface for networks to expose choice in routing traffic to end systems. Because most networks are also business entities, and are sensitive to the cost of routing traffic in their network, this dissertation also develops a framework for exposing paths based on their cost. For this purpose, this dissertation develops a cost model for routing traffic in a network. In particular, this dissertation presents the following contributions: * Design of path bits, a "narrow waist" for multipath routing. Our work ties a large number of multipath routing proposals by creating an interface (path bits) for decoupling the multipath routing protocols implemented by the network and end systems (or other network elements) making a choice for path selection. Path bits permit simple, scalable, and efficient implementations of multipath routing protocols in the network that still provide enough expressiveness for end systems to select alternate paths. We demonstrate that our interface is flexible and leads to efficient network implementations by building prototype implementations on different hardware and software platforms. * Design of path splicing, a multipath routing scheme. We develop, path splicing, a multipath routing technique, which uses random perturbations from the shortest path to create exponentially large number of paths with only a linear increase in state in a network. We also develop a simple interface to enable end systems to make path selection decisions. We present various deployment paths for implementing path splicing in both intradomain and interdomain routing on the Internet. * Design of low cost path-selection framework for a network. Network operators and end systems can have conflicting goals, where the network operators are concerned with saving cost and reducing traffic uncertainty; and end systems favor better performing paths. Exposing choice of routing in the network can thus, create a tension between the network operators and the end systems. We propose a path-selection framework where end systems make path selection decisions based on path performance and networks expose paths to end systems based on their cost to the network. This thesis presents a cost model for routing traffic in a network to enable network operators to reason about "what-if " scenarios and routing traffic on their network.