@article {226, title = {Security Issues in VoIP Telecommunication Networks}, journal = {Handbook on Securing Cyber-Physical Critical Infrastructure: Foundations and Challenges}, year = {2012}, pages = {763{\textendash}789}, abstract = {As VoIP telecommunication networks are becoming popular, more and more VoIP calls are being made to accomplish security critical activities, e.g., E911 services, phone banking. However, the security ramifications of using VoIP have not been fully recognized, and there exists a substantial gap in the understanding of the potential impact of VoIP exploits on the VoIP users. In this chapter, we describe the components and functionalities of non-P2P and P2P VoIP networks and discuss the potential attacks to them such as MITM, spoofing, wiretapping, pharming, etc. We also illustrate a mechanism of using small world network to improve call performance of a P2P VoIP system and evaluate it over the currently deployed OpenVoIP system.}, keywords = {P2P, Security, session initiation protocol, small world networks, telecommunications, voice over IP}, isbn = {978-0-12-415815-3}, doi = {https://doi.org/10.1016/B978-0-12-415815-3.00030-3}, url = {https://www.sciencedirect.com/science/article/pii/B9780124158153000303}, author = {Yang, Xiaohui and Ram Dantu and Wijesekera, Duminda} } @conference {68, title = {Efficiency of Social Connection-based Routing in P2P VoIP Networks}, booktitle = {Proceedings of the 2Nd International Conference on COMmunication Systems and NETworks}, year = {2010}, publisher = {IEEE Press}, organization = {IEEE Press}, address = {Piscataway, NJ, USA}, keywords = {P2P routing, P2P VoIP systems, Social networks, social-network based routing}, isbn = {978-1-4244-5487-7}, url = {http://dl.acm.org/citation.cfm?id=1831443.1831488}, author = {Chandrasekaran, Vikram and Ram Dantu and Gupta, Neeraj and Yang, Xiaohui and Wijesekera, Duminda} } @inbook {77, title = {Small World VoIP}, booktitle = {Mobile Computing, Applications, and Services: Second International ICST Conference, MobiCASE 2010, Santa Clara, CA, USA, October 25-28, 2010, Revised Selected Papers}, year = {2010}, pages = {137{\textendash}155}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

We present the analysis and design of a Small World VoIP system (SW-VoIP) which is geared towards customers that are communicating with their Small World of social contacts. We use the term Small World to refer to the Peer-to-Peer (P2P) network of a client and his contacts both incoming and outbound. We reconstruct the small world of a user by collecting calling patterns over a configurable period of time. We enable user mobility by using a stepwise social identity to an IP address binding propagation model. We propose an efficient algorithm to locate users by electing popular users and leveraging the users closeness. We also introduce a self-stabilized load balancing mechanism to optimize the system performance under heavy network traffic. We evaluate our SW-VoIP system performance by simulating the user{\textquoteright}s lookup process using real-world telephone logs. Our experimental results show that our SW-VoIP system offers a better performance in optimizing the required routing path and reducing the average lookup delay when compared to traditional, non small-world P2P VoIP systems.

}, keywords = {closeness, electing, mobility, optimize, Peer-to-peer, popular, small world, VoIP}, isbn = {978-3-642-29336-8}, doi = {10.1007/978-3-642-29336-8_8}, url = {http://dx.doi.org/10.1007/978-3-642-29336-8_8}, author = {Yang, Xiaohui and Stavrou, Angelos and Ram Dantu and Wijesekera, Duminda}, editor = {Gris, Martin and Yang, Guang} } @article {51, title = {A Testbed for Large Mobile Social Computing Experiments}, journal = {Int. J. Sen. Netw.}, volume = {8}, year = {2010}, pages = {89{\textendash}97}, abstract = {

We present a testbed for mobile social computing that can be used to perform research in security, privacy and context-awareness policies and mechanisms appropriate for a wide range of applications. We compare several mobile platforms and present the rational for our design choices and reasons we chose Android as the primary smartphone for the testbed. We also discuss some of the experiments that can be conducted using this testbed.

}, keywords = {context awareness, mobile communications, mobile computing, mobile devices, Privacy, Security, sensor information, sensors, smartphones, social computing, testbed, ubiquitous devices}, issn = {1748-1279}, doi = {10.1504/IJSNET.2010.034618}, url = {http://dx.doi.org/10.1504/IJSNET.2010.034618}, author = {Alazzawe, Ahmed and Alazzawe, Anis and Wijesekera, Duminda and Ram Dantu} } @conference {64, title = {Achieving Peer-to-peer Telecommunication Services Through Social Hashing}, booktitle = {Proceedings of the 6th IEEE Conference on Consumer Communications and Networking Conference}, year = {2009}, publisher = {IEEE Press}, organization = {IEEE Press}, address = {Piscataway, NJ, USA}, abstract = {

Although peer-to-peer (P2P) Internet Telephony gains more and more market share, supporting traditional telephony related use cases is an indispensable requirement. However, communication services designed for this purpose are usually traditional circuit-based, and the centralized structure makes it nearly impossible for their deployments in a distributed, unsecure telecommunication environment. This paper proposes an approach for achieving various kinds of communication services on P2P voice over IP (VoIP) systems by building trust and executing supervision through social networks. We present a system architecture design for network topology maintenance and security assurance. Social protocols and social computing are used to study how P2P entities can be efficiently mapped to social networks, and how social functionalities can benefit communication services implementation. To demonstrate the approach feasibility, we exemplify this architecture in P2P VoIP emergency services by using gossiping and membership management techniques. We believe that our proposed approach will be able to support diverse services on P2P VoIP systems with the performance and security guaranteed to compete with centralized telecommunication systems.

}, isbn = {978-1-4244-2308-8}, url = {http://dl.acm.org/citation.cfm?id=1700527.1700582}, author = {Yang, Xiaohui and Ram Dantu and Wijesekera, Duminda} } @conference {76, title = {A society-integrated testbed architecture for peer-to-peer telecommunications}, booktitle = {Testbeds and Research Infrastructures for the Development of Networks Communities and Workshops, 2009. TridentCom 2009. 5th International Conference on}, year = {2009}, month = {April}, abstract = {

Exploiting and deploying telecommunication services on Internet Telephony are imperative for a large market share. However, the distributed nature of peer-to-peer (P2P) network makes services implementation very difficult. In order to meet the research goals of achieving P2P telecommunication services through the union of social and computer networks, we present a society-integrated testbed architecture for P2P voice over IP (VoIP). By introducing an architecture that exploits and entailing social structure based connection establishment, the testbed presents an organic integration of social functionalities with good portability. The testbed also serves as a flexible tool suite that can be used to run experiments and obtain timely feedback based on the performance measurements.

}, keywords = {Computer architecture, computer network, computer networks, Computer science, Feedback, file organisation, Internet telephony, network traffic, P2P voice-over-IP, Peer to peer computing, peer-to-peer computing, peer-to-peer telecommunication service, portable social DHT function, Routing protocols, Social network services, society-integrated testbed architecture, software architecture, Telecommunication services, telecommunication traffic, Testing}, doi = {10.1109/TRIDENTCOM.2009.4976215}, author = {Yang, Xiaohui and Ram Dantu and Wijesekera, Duminda} } @conference {55, title = {A testbed for mobile social computing}, booktitle = {Testbeds and Research Infrastructures for the Development of Networks Communities and Workshops, 2009. TridentCom 2009. 5th International Conference on}, year = {2009}, month = {April}, abstract = {

We present a testbed for mobile social computing that can be used to perform research in security, privacy, and context-awareness policies and mechanisms appropriate for a wide range of applications. We compare several mobile platforms and present the rational for our design choices and reasons we chose Android as the primary smartphone for this testbed. We also discuss some of the possible experiments that can be conducted using the testbed.

}, keywords = {Acoustic sensors, Computer science, Computer security, context-awareness policy, data privacy, Feedback, Global Positioning System, mobile computing, mobile social computing, Performance evaluation, Privacy, privacy policy, security of data, security policy, Social network services, Testing}, doi = {10.1109/TRIDENTCOM.2009.4976250}, author = {Alazzawe, Ahmed and Alazzawe, Anis and Wijesekera, Duminda and Ram Dantu} } @conference {33, title = {Securing VoIP and PSTN from integrated signaling network vulnerabilities}, booktitle = {1st IEEE Workshop on VoIP Management and Security, 2006.}, year = {2006}, abstract = {

The liberalization of public switched telephone network (PSTN) and growing acceptance of SIGTRAN protocol suite have introduced new and yet to be trusted signaling entities. Thus security threats emerging from one network not only affects itself but other network also. We show how this integrated signaling environment can become a security threat to emerging VoIP and PSTN networks. We propose a security solution as a fix. Our proposal goes beyond "Gateway Screening" and "SS7 Gatekeeper" proposed by Telcordia and Verizon respectively to defend vulnerable SS7 network.

}, keywords = {Information security, Information systems, Internet telephony, IP networks, ISDN, National security, Protocols, Routing, Signal processing, Switching circuits}, doi = {10.1109/VOIPMS.2006.1638116}, author = {Sengar, Hemant and Ram Dantu and Wijesekera, Duminda} } @article {39, title = {SS7 over IP: signaling interworking vulnerabilities}, journal = {IEEE Network}, volume = {20}, year = {2006}, month = {Nov}, pages = {32-41}, abstract = {

Public telephony - the preferred choice for two-way voice communication over a long time - has enjoyed remarkable popularity for providing acceptable voice quality with negligible connection delays, perhaps due to its circuit-switched heritage. Recently, IP telephony, a packet-based telephone service that runs as an application over the IP protocol, has been gaining popularity. To provide seamless interconnectivity between these two competing services, the Internet Engineering Task Force (IETF) has designed a signaling interface commonly referred to as SIGTRAN. This seamless intersignaling provided by SIGTRAN facilitates any subscriber in one network to reach any other subscriber in the other network, passing through any heterogeneous maze of networks consisting of either of these. Unfortunately, the same intersignaling potentially can be exploited from either side to disrupt the services provided on the other side. We show how this can be done and propose a solution based on access control, signal screening, and detecting anomalous signaling. We argue that to be effective, the latter two should consider syntactic correctness, semantic validity of the signal content, and the appropriateness of a particular signal in the context of earlier exchanged messages

}, keywords = {anomalous signaling detection, circuit-switched heritage, Delay effects, Design engineering, IETF, Integrated circuit interconnections, Internet Engineering Task Force, Internet telephony, intersignaling, IP protocol, ISDN, packet-based telephone service, Protocols, public telephony, Routing, Signal detection, signal screening, signaling interworking, SIGTRAN, SS7 over IP, Switches, telecommunication signalling, two-way voice communication, Web and internet services}, issn = {0890-8044}, doi = {10.1109/MNET.2006.273119}, author = {Sengar, Hemant and Ram Dantu and Wijesekera, Duminda and Jajodia, Sushil} }