Mobility Support in User-Centric Networks

In this paper, an overview of challenges and requirements for mobility management in user-centric networks is given, and a new distributed and dynamic per-application mobility management solution is presented. After a brief summary of generic mobility management concepts, existing approaches from the distributed and peer-to-peer mobility management literature are introduced, along with their applicability or shortcomings in the UCN environment. Possible approaches to deal with the decentralized and highly dynamic nature of UCNs are also provided with a discussion and an introduction to potential future work

Prospects of peer-to-peer SIP for mobile operators

Tämän diplomityön tarkoituksena on esitellä kehitteillä oleva Peer-to-Peer Session Initiation Protocol (P2PSIP), jonka avulla käyttäjät voivat itsenäisesti ja helposti luoda keskenään puhe- ja muita multimediayhteyksiä vertaisverkko-tekniikan avulla. Lisäksi tarkoituksena on arvioida P2PSIP protokollan vaikutuksia ja mahdollisuuksia mobiilioperaattoreille, joille sitä voidaan pitää uhkana. Tästä huolimatta, P2PSIP:n ei ole kuitenkaan tarkoitus korvata nykyisiä puhelinverkkoja. Työn alussa esittelemme SIP:n ja vertaisverkkojen (Peer-to-Peer) periaatteet, joihin P2PSIP-protokollan on suunniteltu perustuvan. SIP mahdollistaa multimedia-istuntojen luomisen, sulkemisen ja muokkaamisen verkossa, mutta sen monipuolinen käyttö vaatii keskitettyjen palvelimien käyttöä. Vertaisverkon avulla käyttäjät voivat suorittaa keskitettyjen palvelimien tehtävät keskenään hajautetusti. Tällöin voidaan ylläpitää laajojakin verkkoja tehokkaasti ilman palvelimista aiheutuvia ylläpito-kustannuksia. Mobiilioperaattorit ovat haasteellisen tilanteen edessä, koska teleliikennemaailma on muuttumassa yhä avoimemmaksi. Tällöin operaattoreiden asiakkaille aukeaa mahdollisuuksia käyttää kilpailevia Internet-palveluja (kuten Skype) helpommin ja tulevaisuudessa myös itse muodostamaan kommunikointiverkkoja P2PSIP:n avulla. Tutkimukset osoittavat, että näistä uhista huolimatta myös operaattorit pystyvät näkemään P2PSIP:n mahdollisuutena mukautumisessa nopeasti muuttuvan teleliikennemaailman haasteisiin. Nämä mahdollisuudet sisältävät operaattorin oman verkon optimoinnin lisäksi vaihtoehtoisten ja monipuolisempien palveluiden tarjoamisen asiakkailleen edullisesti. Täytyy kuitenkin muistaa, että näiden mahdollisuuksien toteuttamisten vaikutusten ei tulisi olla ristiriidassa operaattorin muiden palveluiden kanssa. Lisäksi tulisi muistaa, että tällä hetkellä keskeneräisen P2PSIP-standardin lopullinen luonne ja ominaisuudet voivat muuttaa sen vaikutuksia.The purpose of this thesis is to present the Peer-to-Peer Session Initiation Protocol (P2PSIP) being developed. In addition, the purpose of this thesis is to evaluate the impacts and prospects of P2PSIP to mobile operators, to whom it can be regarded as a threat. In P2PSIP, users can independently and easily establish voice and other multimedia connections using peer-to-peer (P2P) networking. However, P2PSIP is not meant to replace the existing telephony networks of the operators. We start by introducing the principles of SIP and P2P networking that the P2PSIP is intended to use. SIP enables to establish, terminate and modify multimedia sessions, but its versatile exploitation requires using centralized servers. By using P2P networking, users can decentralize the functions of centralized servers by performing them among themselves. This enables to maintain large and robust networks without maintenance costs resulted of running such centralized servers. Telecommunications market is transforming to a more open environment, where mobile operators and other service providers are challenged to adapt to the upcoming changes. Subscribers have easier access to rivalling Internet-services (such as Skype) and in future they can form their own communication communities by using P2PSIP. The results show that despite of these threats, telecom operators can find potential from P2PSIP in concurrence in adaptation to the challenges of the rapidly changing telecom environment. These potential roles include optimization of the network of the operator, but as well roles to provide alternative and more versatile services to their subscribers at low cost. However, the usage of P2PSIP should not conflict with the other services of the operator. Also, as P2PSIP is still under development, its final nature and features may change its impacts and prospects

Exploiting the power of multiplicity: a holistic survey of network-layer multipath

The Internet is inherently a multipath network: For an underlying network with only a single path, connecting various nodes would have been debilitatingly fragile. Unfortunately, traditional Internet technologies have been designed around the restrictive assumption of a single working path between a source and a destination. The lack of native multipath support constrains network performance even as the underlying network is richly connected and has redundant multiple paths. Computer networks can exploit the power of multiplicity, through which a diverse collection of paths is resource pooled as a single resource, to unlock the inherent redundancy of the Internet. This opens up a new vista of opportunities, promising increased throughput (through concurrent usage of multiple paths) and increased reliability and fault tolerance (through the use of multiple paths in backup/redundant arrangements). There are many emerging trends in networking that signify that the Internet's future will be multipath, including the use of multipath technology in data center computing; the ready availability of multiple heterogeneous radio interfaces in wireless (such as Wi-Fi and cellular) in wireless devices; ubiquity of mobile devices that are multihomed with heterogeneous access networks; and the development and standardization of multipath transport protocols such as multipath TCP. The aim of this paper is to provide a comprehensive survey of the literature on network-layer multipath solutions. We will present a detailed investigation of two important design issues, namely, the control plane problem of how to compute and select the routes and the data plane problem of how to split the flow on the computed paths. The main contribution of this paper is a systematic articulation of the main design issues in network-layer multipath routing along with a broad-ranging survey of the vast literature on network-layer multipathing. We also highlight open issues and identify directions for future work

A Presence-Based Architecture for a Gateway to Integrate Vehicular Ad-Hoc Networks (VANETs), the IP Multimedia Subsystems (IMS) and Wireless Sensor Networks (WSNs)

Résumé Le IP Multimedia Subsystems (IMS) est un sujet de recherche qui attire l’attention de la communauté de recherche. Il a comme but de fournir un accès mobile aux différents services internet. Il s’agit d’une architecture de contrôle au-dessus de la couche IP dont le but est de fournir une qualité de service, services intégrés et un système de tarification équitable à travers des interfaces standards. D’autre part, le réseau Ad-hoc de véhicules (VANETs) fournit un nouveau moyen de communication sans-fil entre les véhicules circulants à grande vitesse ainsi que les équipements installés tout au long des côtés de la route. Cette technologie ouvre la porte pour développer des applications diverses comme la génie de trafic, gestion du trafic, diffusion d’information en cas d’urgence pour éviter des situations critiques, divertissement et bien d’autres choses. VANETs forme une sous-classe des réseaux Ad-hoc mobile dont la performance est fortement liée au protocole de routage utilisé dans le réseau. L’intégration des deux technologies, IMS et VANET, permettra de mettre en œuvre de nouveaux services multimédias. Ce mémoire de maîtrise propose une architecture d’une passerelle incorporant ces deux technologies ensemble. Étant donné que les deux architectures utilisent des formats de communication différents, on a conçu un middleware afin d’adapter le format en fonction de la destination et de choisir la meilleur stratégie de livraison d’information entre eux. La passerelle, qui est le cœur de notre architecture, est une couche au-dessus du IMS et le VANET. ----------ABSTRACT On one hand, IP Multimedia Subsystems (IMS) are a research area that has been gaining attention from the research community. It aims to provide cellular access to all Internet services. It is a control architecture on the top of the IP layer whose goal is dependent on the provision of the Quality of Service (QoS), integrated services and fair charging scheme throughout standard interfaces. On the other hand, Vehicular Ad-hoc Networks (VANETs) are a new communication paradigm that enables the wireless communication between vehicles moving with high speeds, as well as the vehicles and the road side equipments found along the roads. This opened the door to develop several new applications like, traffic engineering, traffic management, dissemination of emergency information to avoid critical situations, comfort and entertainment and other user applications. Moreover, VANETs are a sub-class of mobile ad-hoc networks; the performance of the communication depends on how better the routing takes place in the network. Routing of data depends on the routing protocols being used in the network. Combining the capabilities of IMS world with the VANET world opens the door to deploy a wide range of novel multimedia services. This dissertation proposes a presence-based architecture for the integration of IMS with VANETs. The presence of the middleware is used to make an instantaneous awareness of the VANETs changes as well as of the IMS format and to select the best delivery strategy between the two architectures. The gateway which is the heart of our architecture is an overlay built on the top of the IMS as well as the VANETs