Dimitris Geneiatakis

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The open architecture of the Internet and the use of open standards like Session Initiation Protocol (SIP) constitute the provisioning of services (e.g., Internet telephony, instant messaging, presence, etc.) vulnerable to known Internet attacks, while at the same time introducing new security problems based on these standards that cannot been tackled with(More)
Session Initiation Protocol is a core protocol for coming real time communication networks, including VoIP, IMS and IPTV networks. Based on the open IP stack, it is similarly susceptible to Denial-of-Service Attacks launched against SIP servers. More than 20 different research works have been published to address SIP-related DoS problems. In this survey we(More)
The commercial deployment of VoIP necessitates the employment of security mechanisms that can assure availability, reliability, confidentiality and integrity. The Session Initiation Protocol (SIP) is considered as the dominant signalling protocol for calls over the Internet. SIP, like other Internet protocols, is vulnerable to known Internet attacks, while(More)
The advent of Voice over IP (VoIP) has offered numerous advantages but, at the same time, it has introduced security threats not previously encountered in networks with a closed architecture like the Public Switch Telephone Networks (PSTN). One of these threats is that of signaling attacks. This paper examines the signaling attacks in VoIP environments(More)
0140-3664/$ see front matter 2008 Elsevier B.V. A doi:10.1016/j.comcom.2008.03.016 * Corresponding author. Tel.: +49 30 3463 7378; fa E-mail addresses: sven.ehlert@fokus.fraunhofer.de fraunhofer.de (G. Zhang), dgen@aegean.gr (D. Gen (G. Kambourakis), ntan@teimes.gr (T. Dagiuklas), jiri. dorgham.sisalem@tekelec.com (D. Sisalem). The emergence of Voice over(More)
In complex environments like the IP multimedia Subsystem (IMS), state of the art security solutions cannot always provide satisfactory protection against any type of attack. This paper addresses the security mechanisms utilized by IMS with respect to their susceptibility to SIP based attacks that have been described in the literature. This analysis also(More)
Any application or service utilizing the Internet is exposed to both general Internet attacks and other specific ones. Most of the times the latter are exploiting a vulnerability or misconfiguration in the provided service and/or in the utilized protocol itself. Consequently, the employment of critical services, like Voice over IP (VoIP) services, over the(More)
Internet telephony like any other Internet service suffers from security flaws caused by various implementation errors (e.g. in end-users terminals, protocols, operating systems, hardware, etc). These implementation problems usually lead VoIP subsystems (e.g. SIP servers) to various unstable operations whenever trying to process a message not conforming to(More)
DNS amplification attacks massively exploit open recursive DNS servers mainly for performing bandwidth consumption DDoS attacks. The amplification effect lies in the fact that DNS response messages may be substantially larger than DNS query messages. In this paper, we present and evaluate a novel and practical method that is able to distinguish between(More)
It is well known that no security mechanism can provide full protection against a potential attack. There is always a possibility that a security incident may happen, mainly as a result of a new or modified attack that the employed countermeasures cannot handle or identify. It is therefore useful to perform a deferred analysis of logged network data, in an(More)