Communication networks have evolved from circuit-switched and hop-by-hop routed systems into hybrid data/optical networks using the Internet as a common backbone carrying narrow- and broad-band traffic offered by a multitude of access networks. This data/optical backbone is built around a multi-technology/multi-protocol routing architecture which runs the IP protocols in a collapsed IP stack where ATM and SONET/SDH have been replaced by the suite of Generalized Multiprotocol Label Switching (GMPLS) protocols. A further evolution referred to as ``IP over Photons'' or ``All IP - All Optical'' is expected where ``redundant intermediate layers'' will be eliminated to run IP directly on top of optical cross-connects (OXCs) with the expectation of achieving savings on operation expenditures (OPEX) and capital expenditures (CAPEX). ``IP over Photons'' has been stalled by the immaturity in the control and data plane technologies leading to complex and time-consuming manual network planning and configurations which require a group of ``layer experts'' to operate and maintain a hybrid data/optical network. By making the status of each link and node of a data/optical network visible to a common control, GMPLS protocols have opened the way for automated operation and management allowing the different layers of an IP stack to be managed by a single network operator. GMPLS protocols provide the potential to make more efficient use of the IP backbone by having network management techniques such as Traffic Engineering (TE) and Network Engineering (NE), once the preserve of telecommunications, to be reinvented and deployed to effect different Quality of Service (QoS) requirements in the IP networks. NE moves bandwidth to where the traffic is offered to the network while TE moves traffic to where the bandwidth is available to achieve QoS agreements between the current and expected traffic and the available resources. However,several issues need to be resolved before TE and NE be effectively deployed in emerging and next generation IP networks. These include (1) the identification of QoS requirements of the different network layer interfaces of the emerging and next generation IP stack (2) the mapping of these QoS requirements into QoS routing mechanisms and network control strategies and (3) the deployment of these mechanisms and strategies within and beyond an Internet domain's boundaries to maximize the engineering and economic efficiency. Building upon different frameworks and research fields, this thesis revisits the issue of Traffic and Network Engineering (TE and NE) to present and evaluate the performance of different QoS routing mechanisms and network control strategies when deployed at different network layer interfaces of a hybrid data/optical network where an IP over MPLS network is layered above an MP λS/Fiber infrastructure. These include mechanisms and strategies to be deployed at the IP/MPLS, MPLS/MP λS and MP λS/Fiber network layer interfaces. The main contributions of this thesis are threefold. First we propose and compare the performance of hybrid routing approaches to be deployed in IP/MPLS networks by combining connectionless routing mechanisms used by classical IGP protocols and the connection oriented routing approach borrowed from MPLS. Second, we present QoS routing mechanisms and network control strategies to be deployed at the MPLS/MP λS network layer interface with a focus on contention-aware routing and inter-layer visibility to improve multi-layer optimality and resilience. Finally, we build upon fiber transmission characteristics to propose QoS routing mechanisms where the routing in the MPLS and MP λS layers is conducted by Photonic characteristics of the fiber such as the availability of the physical link and its failure risk group probability. / QC 20100630

No description available.

Transformers and storage systems in the electrical grid must be provisioned or sized just as routers and buffers must be sized in the Internet. We prove the formal equivalence between these two systems and use this insight to apply teletraffic theory to sizing the electrical grid, obtaining the capacity region corresponding to a given transformer and storage size. We conduct a fine-grained measurement study of household electrical load. These measurements are essential for two reasons. First, we use them to construct reference models for home loads; these models are used to find the capacity region using the teletraffic theory. Second, these measurements are used in numerical simulations that are done to validate our analysis. More specifically, we compare results of numerical simulations with the results from teletraffic theory. We show not only that teletraffic theory agrees well with numerical simulations but also that it closely matches with the heuristics used in current practice. Moreover, our analysis permits us to develop sizing rules for battery storage electrical grid, advancing the state of the art.

Transformers and storage systems in the electrical grid must be provisioned or sized just as routers and buffers must be sized in the Internet. We prove the formal equivalence between these two systems and use this insight to apply teletraffic theory to sizing the electrical grid, obtaining the capacity region corresponding to a given transformer and storage size. We conduct a fine-grained measurement study of household electrical load. These measurements are essential for two reasons. First, we use them to construct reference models for home loads; these models are used to find the capacity region using the teletraffic theory. Second, these measurements are used in numerical simulations that are done to validate our analysis. More specifically, we compare results of numerical simulations with the results from teletraffic theory. We show not only that teletraffic theory agrees well with numerical simulations but also that it closely matches with the heuristics used in current practice. Moreover, our analysis permits us to develop sizing rules for battery storage electrical grid, advancing the state of the art.

Durante los últimos años las redes móviles celulares han experimentado un considerable crecimiento y desarrollo debido al nuevo modo en que la sociedad crea, comparte y consume información. El enorme impacto y penetración de los servicios móviles telefónicos en la sociedad actual, así como la introducción de un amplio abanico de nuevos servicios de datos y servicios multimedia, han llevado a un crecimiento espectacular del volumen de tráfico transportado por este tipo de redes. Esta tendencia se mantendrá en los próximos años ya que constantemente van apareciendo nuevas aplicaciones que demandan mayor calidad de servicio y ancho de banda. Sin embargo, lasredesmóviles celulares actualestienen fuerteslimitaciones de ancho de banda debido a la escasez de frecuencias en el espectro radioeléctrico. Así, estas nuevas necesidades establecen nuevosretos para la industria de las telecomunicaciones. Es necesario gestionar un creciente número de servicios que demandan elevadas cantidades de recursos, conjuntamente con la escasez del espectro radioeléctrico, para ofrecer servicios que satisfagan las necesidades de los usuarios de un modo eficaz y económico. Dentro de este contexto, la gestión de los recursos radio se presenta como una estrategia clave para hacer frente a las características especiales de estasredes. Concretamente, el control de admisión es un mecanismo clave para utilizar eficientemente los recursos radio disponibles, proporcionando al mismo tiempo las garantías de calidad de servicio requeridas para todoslos usuarios. El presente trabajo se centra en el diseño y evaluación de políticas de control de admisión implementadas en redes móviles celulares multiservicio que transportan diferentes servicios portadores. Además, la presente tesis es una contribución al desarrollo de modelos con los que evaluar diferentes políticas de control de admisión en el desafiante contexto introducido por las redes 4G de próxima aparición. En la primera parte de esta tesis se trata el desarrollo de políticas de control de admisión para redes utilizadas actualmente, mientras que en la segunda parte de esta tesis se proponen políticas de control de admisión novedosas con el objetivo de hacerfrente a los retos introducidos por las redes de próxima aparición, tales como las redes Long TermEvolution o las de tecnología Cognitive Radio / Bernal Mor, E. (2013). Design and evaluation of admission control policies in mobile cellular networks [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/27714 / Alfresco

<p>The GSM network technology has been developed and improved during several years which have led to an increased complexity. The complexity results in more network parameters and together with different scenarios and situations they form a complex set of configurations. The definition of the network parameters is generally a manual process using static values during test execution. This practice can be costly, difficult and laborious and as the network complexity continues to increase, this problem will continue to grow.This thesis presents an implementation of an automated performance optimization algorithm that utilizes genetic algorithms for optimizing the network parameters. The implementation has been used for proving that the concept of automated optimization is working and most of the work has been carried out in order to use it in practice. The implementation has been applied to the Link Quality Control algorithm and the Improved ACK/NACK feature, which is an apart of GSM EDGE Evolution.</p> / <p>GSM-nätsteknologin har utvecklats och förbättrats under lång tid, vilket har lett till en ökad komplexitet. Denna ökade komplexitet har resulterat i fler nätverksparameterar, tillstånd och standarder. Tillsammans utgör de en komplex uppsättning av olika konfigurationer. Dessa nätverksparameterar har hittills huvudsakligen bestämts med hjälp av en manuell optimeringsprocess. Detta tillvägagångssätt är både dyrt, svårt och tidskrävande och allt eftersom komplexiteten av GSM-näten ökar kommer problemet att bli större.Detta examensarbete presenterar en implementering av en algoritm för automatiserad optimering av prestanda som huvudsakligen använder sig av genetiska algoritmer för att optimera värdet av nätverksparametrarna. Implementeringen har använts för att påvisa att konceptet med en automatiserad optimering fungerar och det mesta av arbetet har utförts för att kunna använda detta i praktiken. Implementeringen har tillämpats på Link Quality Control-algoritmen och Improved ACK/NACK-funktionaliteten, vilket är en del av GSM EDGE Evolution.</p>

<p>The new mobile standard Long Term Evolution delivers high data rates, small delay and a more efficiently utilized RF spectrum. A solution to maintain this performance in user dense areas or areas with bad reception is the deployment of so-called femtocells. Femtocells are small base stations that are deployed indoors and share the RF spectrum with the whole mobile network. The idea is that femtocells will increase mobile operators network coverage and capacity while it at the same time increase users data throughput. There are several challenges with femtocells, both technical and economical ones. The most debated issues is how femtocells should schedule users while operating in an environment where other femtocells and base stations are interfering. In this work we developed a simulation tool to simulate the scheduling interaction between femtocells and base stationsin order to show the performance of radio resource schedulers. This rapport also aims to evaluate an approach to a femtocell scheduler to solve this issue in a satisfying way. The report gives a description of the structure of the implemented simulation tool together with some reflections on how future designs of similar or more complex simulation environments could be done.</p>

The GSM network technology has been developed and improved during several years which have led to an increased complexity. The complexity results in more network parameters and together with different scenarios and situations they form a complex set of configurations. The definition of the network parameters is generally a manual process using static values during test execution. This practice can be costly, difficult and laborious and as the network complexity continues to increase, this problem will continue to grow.This thesis presents an implementation of an automated performance optimization algorithm that utilizes genetic algorithms for optimizing the network parameters. The implementation has been used for proving that the concept of automated optimization is working and most of the work has been carried out in order to use it in practice. The implementation has been applied to the Link Quality Control algorithm and the Improved ACK/NACK feature, which is an apart of GSM EDGE Evolution. / GSM-nätsteknologin har utvecklats och förbättrats under lång tid, vilket har lett till en ökad komplexitet. Denna ökade komplexitet har resulterat i fler nätverksparameterar, tillstånd och standarder. Tillsammans utgör de en komplex uppsättning av olika konfigurationer. Dessa nätverksparameterar har hittills huvudsakligen bestämts med hjälp av en manuell optimeringsprocess. Detta tillvägagångssätt är både dyrt, svårt och tidskrävande och allt eftersom komplexiteten av GSM-näten ökar kommer problemet att bli större.Detta examensarbete presenterar en implementering av en algoritm för automatiserad optimering av prestanda som huvudsakligen använder sig av genetiska algoritmer för att optimera värdet av nätverksparametrarna. Implementeringen har använts för att påvisa att konceptet med en automatiserad optimering fungerar och det mesta av arbetet har utförts för att kunna använda detta i praktiken. Implementeringen har tillämpats på Link Quality Control-algoritmen och Improved ACK/NACK-funktionaliteten, vilket är en del av GSM EDGE Evolution.

The new mobile standard Long Term Evolution delivers high data rates, small delay and a more efficiently utilized RF spectrum. A solution to maintain this performance in user dense areas or areas with bad reception is the deployment of so-called femtocells. Femtocells are small base stations that are deployed indoors and share the RF spectrum with the whole mobile network. The idea is that femtocells will increase mobile operators network coverage and capacity while it at the same time increase users data throughput. There are several challenges with femtocells, both technical and economical ones. The most debated issues is how femtocells should schedule users while operating in an environment where other femtocells and base stations are interfering. In this work we developed a simulation tool to simulate the scheduling interaction between femtocells and base stationsin order to show the performance of radio resource schedulers. This rapport also aims to evaluate an approach to a femtocell scheduler to solve this issue in a satisfying way. The report gives a description of the structure of the implemented simulation tool together with some reflections on how future designs of similar or more complex simulation environments could be done.

Η παρούσα διδακτορική διατριβή πραγματεύεται την ανάλυση και προσομοίωση των συστημάτων απωλειών πολυδιάστατης τηλεπικοινωνιακής κίνησης, σε επίπεδο κλήσεων. Στα πλαίσια της διατριβής έχουν μελετηθεί ασύρματα δίκτυα τεχνολογίας W-CDMA, ενσύρματα συνδεσιμοστρεφή δίκτυα και οπτικά δίκτυα. Ιδιαίτερη έμφαση δόθηκε στα ασύρματα δίκτυα. Η ανάλυση των συστημάτων απωλειών κίνησης εξαρτάται κατά κύριο λόγο από τις διαδικασίες άφιξης και εξυπηρέτησης των κλήσεων. Στην διδακτορική αυτή διατριβή προτείνονται οκτώ νέα μοντέλα απωλειών κλήσεων. Τα έξη από αυτά είναι κατάλληλα για την ανάλυση της απόδοσης σε επίπεδο κλήσεων των ασύρματων δικτύων τεχνολογίας W-CDMA. Τα υπόλοιπα δύο είναι γενικά μοντέλα, κατάλληλα για ενσύρματα συνδεσιμοστρεφή τηλεπικοινωνιακά δίκτυα και οπτικά δίκτυα. Ανάλογα με την διαδικασία άφιξης των κλήσεων στο σύστημα, διακρίνουμε δύο είδη κίνησης: τυχαία και ψευδο-τυχαία. Η τυχαία κίνηση παράγεται όταν η διαδικασία άφιξης των κλήσεων στο σύστημα είναι Poisson. Αυτό αντιστοιχεί στην υπόθεση ότι έχουμε άπειρο πλήθος πηγών που παράγουν κλήσεις. Όταν το πλήθος των πηγών είναι πεπερασμένο, τότε παράγεται ψευδο-τυχαία κίνηση. Ανάλογα με τις απαιτήσεις των κλήσεων σε πόρους και σε χρόνο εξυπηρέτησης κατά την άφιξή τους στο σύστημα, διακρίνουμε τρία είδη κίνησης: σταθερή, ελαστική και προσαρμοζόμενη. Η σταθερή κίνηση παράγεται από κλήσεις που έχουν σταθερές απαιτήσεις σε πόρους και σε χρόνο εξυπηρέτησης. Η ελαστική και η προσαρμοζόμενη κίνηση παράγεται από κλήσεις που μπορούν να έχουν διαφορετικές, εναλλακτικές απαιτήσεις σε πόρους, ανάλογα με την διαθεσιμότητα των πόρων στο σύστημα. Ανάλογα με την συμπεριφορά των κλήσεων μετά την αποδοχή τους στο σύστημα, διακρίνουμε: α) κλήσεις που κατά την διάρκεια της εξυπηρέτησης δεν μπορούν να μεταβάλουν το εύρος ζώνης που τους έχει ανατεθεί (σταθερός ρυθμός μετάδοσης), και β) κλήσεις που κατά την διάρκεια της εξυπηρέτησης μπορούν να μεταβάλουν το εύρος ζώνης (ελαστικός ρυθμός μετάδοσης) προκειμένου το σύστημα να μπορεί να δεχτεί και άλλες κλήσεις. / In this PhD dissertation new multi-rate teletraffic loss models are developed for the call-level analysis of wireless W-CDMA networks, connection-oriented networks and optical networks. The model's accuracy and consistency are verified by simulation and found to be very satisfactory. The analysis of loss systems mainly depends on the call arrival and call service processes. Eight new teletraffic loss models are proposed. Six of them are suitable for the call-level performance analysis of W-CDMA networks, while the other two models are more general and suitable for the analysis of either connection-oriented networks or optical networks. According to the call arrival process, we distinguish two types of traffic: random and quasi-random. Random traffic is generated when the call arrival process is Poisson. This coincides with the assumption that the number of traffic sources is infinite. When the number of traffic sources is finite, we have the so called quasirandom traffic. According to the calls’ resource and service time requirements, we distinguish three types of traffic: stream, elastic and adaptive. Stream traffic is generated by calls that have fixed resource and service time requirements. Elastic and adaptive traffic is generated by calls that may have alternative contingency resource requirements depending on the resource availability or the capacity of the system. According to the calls’ behaviour after their acceptance into the system, we distinguish: a) calls that during their service time are not able to change the number of allocated resources (constant transmission rate) and b) calls that during their service time are able to change the number of allocated resources (elastic transmission rate) in order for the system to be able to accept more calls.