Comparing Interconnecting Methods for Multiprotocol Label Switched Virtual Private Networks

Operaattorit tarjoavat leimakytkentää hyödyntäviä virtuaaliverkkopalveluita asiakkailleen. Lisäksi operaattorit hyödyntävät niitä omien palveluidensa tuottamisessa. Sekä leimakytkentä että sitä hyödyntävät virtuaaliverkkopalvelut on määritelty toimiviksi yhden autonomisen alueen sisällä. Tässä työssä vertaillaan neljää erilaista tapaa liittää virtuaaliverkot toimimaan yli AS-rajojen. Vertailu tehdään tietoturvallisuuden näkökulmasta. Työssä paneudutaan kolmeen eri virtuaaliverkkopalveluun ja siihen, miten näiden toteutustekniikat vaikuttavat yhteenliittämiseen. Vertailu on pyritty tekemään niin, että se on sovellettavissa kaikille palveluille. Kaikilta osilta näin ei ole, sillä palveluiden toteutustavat poikkeavat liikaa toisistaan. Vertailu paljasti, että yhteenliittämistavoilla on erilaisia vahvuuksia tietoturvan suhteen. Yhteenliittämistapaa valitessa operaattorin tulee määritellä, mitä tietoturvauhkia painottaa. Osa tietoturvauhista johtuu laitevalmistajien toteutuksien heikkouksista, mutta osa on standardeille ominaisia. Tietoturvariskit tiedostaen, ja ottamalla huomioon yhteenliittämisen aiheuttamat lisäriskit tietoturvalle, operaattorin on mahdollista tarjota tietoturvallisia leimakytkentäisiä virtuaaliverkkopalveluita, jotka kattavat useamman autonomisen alueen.Telecommunication operators offer Multiprotocol Label Switched Virtual Private Networks to their customers. Also, MPLS VPN technologies can be used for operators' internal purposes, to enable them to offer wider range of services in single infrastructure. Both MPLS and MPLS based VPNs are defined to be used inside single autonomous system, AS. The aim of this thesis is to compare four different interconnection methods for MPLS VPNs in different AS's. The focus is on security. Three different MPLS VPN services are looked into closely. Each service's technology's effect on interconnection is of interest. The comparison tries to incorporate all three services. But, since the services differ from each other, not all criteria concern all services. The comparison revealed that the interconnection methods have different strengths concerning security. When choosing the interconnection method, an operator needs to define what areas of security it finds relevant. A portion of security issues are implementation specific, but some come directly from the standards. When operator is aware of the security issues related to chosen interconnection method, it is safe to offer MPLS VPNs that cover multiple autonomous systems

Next generation control of transport networks

It is widely understood by telecom operators and industry analysts that bandwidth demand is increasing dramatically, year on year, with typical growth figures of 50% for Internet-based traffic [5]. This trend means that the consumers will have both a wide variety of devices attaching to their networks and a range of high bandwidth service requirements. The corresponding impact is the effect on the traffic engineered network (often referred to as the “transport network”) to ensure that the current rate of growth of network traffic is supported and meets predicted future demands. As traffic demands increase and newer services continuously arise, novel network elements are needed to provide more flexibility, scalability, resilience, and adaptability to today’s transport network. The transport network provides transparent traffic engineered communication of user, application, and device traffic between attached clients (software and hardware) and establishing and maintaining point-to-point or point-to-multipoint connections. The research documented in this thesis was based on three initial research questions posed while performing research at British Telecom research labs and investigating control of transport networks of future transport networks: 1. How can we meet Internet bandwidth growth yet minimise network costs? 2. Which enabling network technologies might be leveraged to control network layers and functions cooperatively, instead of separated network layer and technology control? 3. Is it possible to utilise both centralised and distributed control mechanisms for automation and traffic optimisation? This thesis aims to provide the classification, motivation, invention, and evolution of a next generation control framework for transport networks, and special consideration of delivering broadcast video traffic to UK subscribers. The document outlines pertinent telecoms technology and current art, how requirements I gathered, and research I conducted, and by which the transport control framework functional components are identified and selected, and by which method the architecture was implemented and applied to key research projects requiring next generation control capabilities, both at British Telecom and the wider research community. Finally, in the closing chapters, the thesis outlines the next steps for ongoing research and development of the transport network framework and key areas for further study