VoIP/SIP is taking place of conventional telephony because of very low call charge but it is also attractive for SPITters who advertise or spread phishing calls toward many callees. Although there exist many feature-based SPIT detection methods, none of them provides the flexibility against multiple features and thus complex threshold settings and training phases cannot be avoided. In this pape...

Spam over Internet Telephony (SPIT) is a potential source of disruption in Voice over IP (VoIP) systems. The use of anti-SPIT mechanisms, such as filters and audio CAPTCHA (Completely Automated Public Turing Test to Tell Computer and Humans Apart) can prevent

The Security threats to current circuit switched networks dedicated to a single voice application such as the Public Switched Telephone Network (PSTN) are considered minimal. However, in open environments such as the Internet, conducting an attack on voice applications such as Voice over IP (VoIP) is much simpler. This is because VoIP services such as Session Initiation Protocol (SIP) are using...

The Session Initiation Protocol (SIP) has become the most predominant protocol for Voice over Internet Protocol (VoIP) signaling. Security of SIP is an important consideration for VoIP communication as the traffic is transmitted over the insecure IP network. And the authentication process in SIP ranges from preshared secret based solutions to Public Key Infrastructure (PKI) based solution. Howe...

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 based on the Session Initiation Protocol (...

Quality of service (QoS) has been a feature of voice communication networks almost since their inception. The extension of traditional voice QoS methods to data communication networks and the Internet has been a longstanding research topic, although for many years it was not considered a critical issue due to the inherent differences between data and voice traffic and the relatively low cost of...

The Session Initiation Protocol (SIP) is commonly used to establish Voice over IP (VoIP) calls. Mostly recently, Yoon et al. proposed a new secure and efficient SIP authentication scheme in a converged VoIP network based on ECC. In this paper, we first demonstrate that the recently proposed SIP authentication scheme is insecure against off-line password guessing attacks. Thereafter, we propose ...

As a result of its low costs and high degree of integration with other services, Voice over Internet Protocol (VoIP) has become very widely used, while Session Initiation Protocol (SIP) is one of the most important protocols for providing the VoIP service. Since SIP is an open source code with a simple structure and high expansibility, SIP servers are more vulnerable to attack by SIP messages m...

As a result of its low costs and high degree of integration with other services, Voice over Internet Protocol (VoIP) has become very widely used, while Session Initiation Protocol (SIP) is one of the most important protocols for providing the VoIP service. Since SIP is an open source code with a simple structure and high expansibility, SIP servers are more vulnerable to attack by SIP messages m...