Signaling Security in LTE Roaming

LTE (Long Term Evolution) also known as 4G, is highly in demand for its incomparable levels of experience like high data rates, low latency, good Quality of Services(QoS) and roaming features. LTE uses Diameter protocol, which makes LTE an all IP network, connecting multiple network providers, providing flexibility in adding nodes and flexible mobility management while roaming. Which in turn makes LTE network more vulnerable to malicious actors. Diameter protocol architecture includes many nodes and the communication between the nodes is done through request and answer messages. Diameter manages the control session. Control session includes the signaling traffic which consists of messages to manage the user session. Roaming signaling traffic arises due to subscribers movement out of the geographical range of their home network to any other network. This signaling traffic moves over the roaming interconnection called S9 roaming interface. This thesis project aims to interfere and manipulate traffic from both user-to-network and network-to-network interfaces in order to identify possible security vulnerabilities in LTE roaming. A fake base-station is installed to establish a connection to a subscriber through the air interface. The IMSI (International Mobile Subscription Identity) is captured using this fake station. To explore the network-to-network communication an emulator based LTE testbed is used. The author has investigated how Diameter messages can be manipulated over the S9 interface to perform a fraud or DoS attack using the IMSI number. The consequences of such attacks are discussed and the countermeasures that can be considered by the MNOs (Mobile Network Operators) and Standardization Committees

Ethernet - a survey on its fields of application

During the last decades, Ethernet progressively became the most widely used local area networking (LAN) technology. Apart from LAN installations, Ethernet became also attractive for many other fields of application, ranging from industry to avionics, telecommunication, and multimedia. The expanded application of this technology is mainly due to its significant assets like reduced cost, backward-compatibility, flexibility, and expandability. However, this new trend raises some problems concerning the services of the protocol and the requirements for each application. Therefore, specific adaptations prove essential to integrate this communication technology in each field of application. Our primary objective is to show how Ethernet has been enhanced to comply with the specific requirements of several application fields, particularly in transport, embedded and multimedia contexts. The paper first describes the common Ethernet LAN technology and highlights its main features. It reviews the most important specific Ethernet versions with respect to each application field’s requirements. Finally, we compare these different fields of application and we particularly focus on the fundamental concepts and the quality of service capabilities of each proposal

Internet Interconnection Ecosystem in Finland

For both fixed and mobile network operators, interconnection constitutes an indisputably key element to provide end users with a variety of services. Internet interconnection is particularly an intriguing subject due to the importance of the Internet in our everyday lives and our genuine curiosity to grasp its underlying structure. This thesis aims to provide a holistic approach to study the Internet interconnections in a nation-centric stance. To accomplish the objective, initially the method that breaks down the key features of the interconnection analysis is introduced. The nation-centric analysis is conducted for Finland by jointly utilizing the Internet registry data and collected Internet routing data. Covering the last decade of the Finnish Internet, the longitudinal analysis yields significant findings for the Internet address usage statistics and the level of multi-homed networks, along with the classification and inference of relationships between stakeholders in the interconnection ecosystem. The implications that the emerging interconnection models pose for the future global service delivery among both fixed and mobile networks are expounded from the perspective of the existing domestic interconnection practices. The longitudinal interconnectivity study allows us to comprehend both technical and business interfaces between market players by revealing a complete list of customer-provider relationships. Within a national milieu, the assessment of the current Internet market dynamics and future implications of emerging models can be considered in more rationally anticipated manner. Hence, authorities who desire to design new pricing schemes and policies for future networking interconnections can be guided more thoroughly

Applicability of SDN and NFV techniques for a virtualization-based roaming solution

Part of a collection: Software-Defined Networking (SDN) and Network Function Virtualization (NFV) for a Hyperconnected World: Challenges, Applications, and Major Advancements.Network programming and virtualization are technological trends being incrementally introduced in operational networks. This creates an environment where new innovations can be incorporated, facilitating also the evolution of the way in which existing services are delivered. These changes, however, are not only motivated by technical reasons. External factors, such as regulation, can trigger the evolution of existing services. Roaming services are an example of this two-sided situation. From the technical perspective, roaming users typically experiment worst performance than local users on the same network, since their traffic is usually routed through the home network. Besides that, due to recent regulation changes introduced in Europe for roaming services, known as Roam Like at Home (RLAH), roaming is charged at domestic prices. Both aspects are severely challenging the current mode of operation of roaming services as delivered nowadays by mobile operators. This paper presents the design of a virtualized based roaming solution, including an experimental assessment, as well as an economic insight of the concept.This work has been supported by the European Community through the 5GEx project within the H2020 programme (Grant agreement no. 671636). Special thanks to the teams of Deutsche Telekom and BISDN involved in H2020 EU 5GEx project that were part of the design and execution of this use case

Progressive introduction of network softwarization in operational telecom networks: advances at architectural, service and transport levels

Technological paradigms such as Software Defined Networking, Network Function Virtualization and Network Slicing are altogether offering new ways of providing services. This process is widely known as Network Softwarization, where traditional operational networks adopt capabilities and mechanisms inherit form the computing world, such as programmability, virtualization and multi-tenancy. This adoption brings a number of challenges, both from the technological and operational perspectives. On the other hand, they provide an unprecedented flexibility opening opportunities to developing new services and new ways of exploiting and consuming telecom networks. This Thesis first overviews the implications of the progressive introduction of network softwarization in operational networks for later on detail some advances at different levels, namely architectural, service and transport levels. It is done through specific exemplary use cases and evolution scenarios, with the goal of illustrating both new possibilities and existing gaps for the ongoing transition towards an advanced future mode of operation. This is performed from the perspective of a telecom operator, paying special attention on how to integrate all these paradigms into operational networks for assisting on their evolution targeting new, more sophisticated service demands.Programa de Doctorado en Ingeniería Telemática por la Universidad Carlos III de MadridPresidente: Eduardo Juan Jacob Taquet.- Secretario: Francisco Valera Pintor.- Vocal: Jorge López Vizcaín

Analysis and Experimental Verification of Diameter Attacks in Long Term Evolution Networks

In cellular networks, the roaming interconnection was designed when there were only a few trusted parties and security was not a major concern or design criteria. Most of the roaming interconnections today are still based on the decades-old SS7 and the lack of security is being blamed for several vulnerabilities. Recent research indicates that the roaming interconnection has been widely misused for gaining access to the core network. Several attacks have been demonstrated by malicious attackers and other unauthorized entities such as intelligence agencies by exploiting the SS7 signaling protocol. Some operators moved to the more modern LTE (Long Term Evolution) and Diameter Signaling for high-speed data roaming and enhanced security. While LTE offers very high quality and resilience over the air security, it still requires special security capabilities and features to secure the core network against attacks targeting the roaming interconnection. This thesis analyses and identifies attacks that exploit the roaming interconnection and Diameter signaling used in LTE networks. The attacks are analyzed in accordance with the mobile network protocol standards and signaling scenarios. The attacks are also implemented in a test LTE network of a global operator. This thesis also focuses on potential countermeasures to mitigate the identified attacks

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

Technology Directions for the 21st Century

New technologies will unleash the huge capacity of fiber-optic cable to meet growing demands for bandwidth. Companies will continue to replace private networks with public network bandwidth-on-demand. Although asynchronous transfer mode (ATM) is the transmission technology favored by many, its penetration will be slower than anticipated. Hybrid networks - e.g., a mix of ATM, frame relay, and fast Ethernet - may predominate, both as interim and long-term solutions, based on factors such as availability, interoperability, and cost. Telecommunications equipment and services prices will decrease further due to increased supply and more competition. Explosive Internet growth will continue, requiring additional backbone transmission capacity and enhanced protocols, but it is not clear who will fund the upgrade. Within ten years, space-based constellations of satellites in Low Earth orbit (LEO) will serve mobile users employing small, low-power terminals. 'Little LEO's' will provide packet transmission services and geo-position determination. 'Big LEO's' will function as global cellular telephone networks, with some planning to offer video and interactive multimedia services. Geosynchronous satellites also are proposed for mobile voice grade links and high-bandwidth services. NASA may benefit from resulting cost reductions in components, space hardware, launch services, and telecommunications services