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This paper provides an approach of how SIP-based multimedia services can be ported to ad hoc networks. This technique achieves two main results: first, it overcomes the lack of existing infrastructure, which is the major handicap for service provision in ad hoc networks. Second, it endows the network with a robust security mechanism to protect the privacy of the undertaken communications

Sip service providers and the spam problem

The Session Initiation Protocol (SIP) is used for managing multimedia sessions in the Internet. As an emerging standard gaining more and more acceptance within the IT community, SIP will probably be the target of spammers. We propose, in this paper, a reputation-based mechanism that builds trust between users within a SIP community and prevents spammers to carry out attacks. Our technique uses a social networks approach enhanced with some reputation ratings. A metric for computing reputation is defined and an algorithm allowing the users to evaluate each other is also presented.

An open testbed for diameter networks

The recent deployment of LTE and IMS networks was not always beneficial. It also introduced new challenges for mobile network operators, researchers and industry experts. To be more precise, the dominant usage of the Diameter protocol in mobile signaling networks is getting increasing consideration in terms of interoperability, scalability and security. This paper briefly presents significant efforts to mitigate such challenges. Moreover, a new testbed for testing, evaluating the usage of Diameter in LTE-IMS mobile networks is introduced. In the testbed, the main components are either implemented by ourselves or collected from existing open source software solutions. By using a generic approach for Diameter provisioning, the testbed is open to new components and new Diameter applications

Addressing security issues in the autonomic Future Internet

We witness an ongoing intensive research towards the specification and implementation of autonomic behaviors for the Future Internet. Important issues that need to be addressed in that context are related to diverse security aspects of the emerging autonomic network technologies. In this paper, we present our research on security in autonomic networks based on the GANA reference model. We present a number of concepts and show how security can be addressed on the architectural level in an autonomic network

EMYNOS: Next Generation Emergency Communication

Current emergency systems and 112 services are based on legacy telecommunication technologies, which cannot cope with IP-based services that European citizens use every day. Some of the related limitations are the partial media support, the lack of integration of social media, and the use of an analogue modem for providing emergency Call (eCall) services with limited data amount. As most operators have started migrating towards broadband IP-based infrastructures, current emergency systems need also to be upgraded and adapted in order to fulfil regulatory requirements in terms of next generation emergency services. This paper present EMYNOS project which aims to the design and implementation of a Next Generation platform capable of accommodating rich-media emergency calls that combine voice, text, and video, thus constituting a powerful tool for coordinating communication among citizens, call centers and first responders. Additionally, issues such as call routing/redirection to the closest-available call center, retrieval of the caller location, support for people with disabilities, and integration of social media will be detailed

A diameter-based testing system in next generation mobile network

Diameter protocol is getting more and more important roles in Next Generation Mobile Network Infrastructure. However, in many cases Diameter interfaces are still under standardization. In this paper, we introduce a flexible Diameter based testing system. The strong point of this system is the capability to keep up with the development of Diameter related standards. It is also friendly, scalable and extensible. This system as well as the OpenEPC testbed are in the series of ongoing research and development activities at Fraunhofer Institute FOKUS, Germany

SIP proxies: New reflectors in the internet

To mitigate identity theft in SIP networks, an inter-domain authentication mechanism based on certificates is proposed in RFC 4474 [10]. Unfortunately, the design of the certificate distribution in this mechanism yields some vulnerabilities. In this paper, we investigate an attack which exploits SIP infrastructures as reflectors to bring down a web server. Our experiments demonstrate that the attacks can be easily mounted. Finally, we discuss some potential methods to prevent this vulnerability

SPIDER: A platform for managing SIP-based Spam over Internet Telephony (SPIT)

The Session Initiation Protocol (SIP) has become the first widely adopted protocol for managing IP-based telephony, video, and multimedia sessions. SIP advertises a contact point of an individual to the Web. This contact point, similar to an e-mail address, can be exploited for spam purposes. Spam over Internet Telephony, also called SPIT, in general denotes any bulk unsolicited information sent to any potential calling-end of a VoIP infrastructure. Even though SPIT is a new concept, it is more reasonable to address this problem right now, rather than waiting until the problem prevails. To mitigate SPIT, adequate technical countermeasures are required. The solution space may expand to nontechnical ones, as well. In this paper, we propose the SPIDER (SPam over Internet telephony Detection sERvice) platform, a modular and efficient system for fighting SPIT. SPIDER orchestrates several discrete modules that parse, analyze, process, and classify incoming SIP call requests. We discuss technical design details of the individual modules, that this platform consists of; then, we present how these modules are combined to support accurate decisions for any incoming SIP call being legitimate or not. Furthermore, we include a comprehensive evaluation scenario, which refers to the tests performed on the individual modules and on the integrated platform. Evaluation results indicate that the overall architecture manages to identify SPIT calls with low false ratio by using reasonable processing resources and tolerable decision time

Performance comparison of the neuron routing algorithm for mobile ad hoc networks

This paper proposes a strong research interest in a field related to bioinformatics and computational biology in Mobile Ad Hoc Networks (MANET). Basically, we develop an intelligent mobile agent called the NEURAL Agent, which improves the performance of the NEUron Routing ALgorithm (NEURAL). This autonomous agent coordinates the gathering of information by integrating, planning, scheduling, and making decision procedures with other agents through different modules that operate asynchronously. In addition, a comparison study is carried out based on the performance of the Dynamic Source Routing (DSR), and the AdHoc OnDemand Distance Vector Routing (AODV)