Covert Channels in SIP for VoIP signalling

In this paper, we evaluate available steganographic techniques for SIP (Session Initiation Protocol) that can be used for creating covert channels during signaling phase of VoIP (Voice over IP) call. Apart from characterizing existing steganographic methods we provide new insights by introducing new techniques. We also estimate amount of data that can be transferred in signalling messages for typical IP telephony call.Comment: 8 pages, 4 figure

Detecting Selected Network Covert Channels Using Machine Learning

International audienceNetwork covert channels break a computer's security policy to establish a stealthy communication. They are a threat being increasingly used by malicious software. Most previous studies on detecting network covert channels using Machine Learning (ML) were tested with a dataset that was created using one single covert channel tool and also are ineffective at classifying covert channels into patterns. In this paper, selected ML methods are applied to detect popular network covert channels. The capacity of detecting and classifying covert channels with high precision is demonstrated. A dataset was created from nine standard covert channel tools and the covert channels are then accordingly classified into patterns and labelled. Half of the generated dataset is used to train three different ML algorithms. The remaining half is used to verify the algorithms' performance. The tested ML algorithms are Support Vector Machines (SVM), k-Nearest Neighbors (k-NN) and Deep Neural Networks (DNN). The k-NN model demonstrated the highest precision rate at 98% detection of a given covert channel and with a low false positive rate of 1%

New security and control protocol for VoIP based on steganography and digital watermarking

In this paper new security and control protocol for Voice over Internet Protocol (VoIP) service is presented. It is the alternative for the IETF's (Internet Engineering Task Force) RTCP (Real-Time Control Protocol) for real-time application's traffic. Additionally this solution offers authentication and integrity, it is capable of exchanging and verifying QoS and security parameters. It is based on digital watermarking and steganography that is why it does not consume additional bandwidth and the data transmitted is inseparably bound to the voice content.Comment: 8 pages, 4 figures, 1 tabl

Secure Data Transmission by using Steganography

Steganography is the efficient technique to provide secure data transmission over the network, as the number of users increases effectively. The cryptography is also used to provide security to data over network, but transmission of secured message may be detectable to third party. From security point of view, steganography does not allow to detect the presence of hidden secret other than indeed user, over the communication channel. In this paper, we design a system, which uses features of both cryptography as well as steganography, where TCP/IP header is used as a steganographic carrier to hide encrypted data. Steganography is a useful tool that allows covert transmission of information over the communications channel. Copyright © www.iiste.org Keywords: Steganography, Cryptography, Encryption, TCP/I

COVERT CHANNEL TECHNIQUE BASED ON STREAMING PROTOCOL

The paper presents analysis of modern network covert channels. The authors set forward a hypothesis of effective streaming protocol usage for covert channel creating. Covert channel technique for open networks is proposed. RTP-based covert channel functional model is described. Estimated characteristics of software prototype are reported. The results of stegano system software prototype operational testing in laboratory conditions and the Internet are described. Software prototype demonstrated high covertness with allowable capacity for many tasks. At the same time transfer characteristics decrease with the complication of network topology. Obtained research results have two application domains of prime importance. On the one hand, illegal covert channel detection methods can be used by DLP-systems developers, law-enforcement agencies and defense establishments. On the other hand, the proposed method for covert information transmission can be used in telemetered covert channel creation, for example, satellite communicatio

SecMon: End-to-End Quality and Security Monitoring System

The Voice over Internet Protocol (VoIP) is becoming a more available and popular way of communicating for Internet users. This also applies to Peer-to-Peer (P2P) systems and merging these two have already proven to be successful (e.g. Skype). Even the existing standards of VoIP provide an assurance of security and Quality of Service (QoS), however, these features are usually optional and supported by limited number of implementations. As a result, the lack of mandatory and widely applicable QoS and security guaranties makes the contemporary VoIP systems vulnerable to attacks and network disturbances. In this paper we are facing these issues and propose the SecMon system, which simultaneously provides a lightweight security mechanism and improves quality parameters of the call. SecMon is intended specially for VoIP service over P2P networks and its main advantage is that it provides authentication, data integrity services, adaptive QoS and (D)DoS attack detection. Moreover, the SecMon approach represents a low-bandwidth consumption solution that is transparent to the users and possesses a self-organizing capability. The above-mentioned features are accomplished mainly by utilizing two information hiding techniques: digital audio watermarking and network steganography. These techniques are used to create covert channels that serve as transport channels for lightweight QoS measurement's results. Furthermore, these metrics are aggregated in a reputation system that enables best route path selection in the P2P network. The reputation system helps also to mitigate (D)DoS attacks, maximize performance and increase transmission efficiency in the network.Comment: Paper was presented at 7th international conference IBIZA 2008: On Computer Science - Research And Applications, Poland, Kazimierz Dolny 31.01-2.02 2008; 14 pages, 5 figure

Стеганографическое скрытие информации при передаче данных

В последнее десятилетие, в связи с широким распространением информационных технологии и необходимостью защиты важной информации, появился интерес к стеганографическим методам защиты информации. В данной статье описаны основные понятия и принципы построения стегано-графических систем, а также рассматривается применение стеганографических методов в сетевых протоколах передачи данных