To counter the threat of leaks of sensitive and mission-critical information, high-security facilities employ multi-level security mechanisms in which information flows are prevented from high-security systems to lower-security systems. For networks, this includes the monitoring of all incoming and outgoing traffic, high-grade encryption for all data communication, intrusion detection systems, ...

171 Application of Unique View Consistency for Elimination of Covert Channels in Real-Time Secure Transaction Processing Systems Namgyu Kim and Songchun Moon Database Laboratory, Department of Management Engineering, Korea Advanced Institute of Science and Technology, Graduate School of Management, 207-43 Cheongryangri-dong, Dongdaemungu, Seoul 130-012 Korea Email: [email protected] Email: scmoon...

Authentication over a network is an important and difficult problem. Accurately determining the authenticity of a node or user is critical in maintaining the security of a network. Our proposed technique covertly embeds a watermark, or identifying tag, within a data stream. By implementing this model on a LAN and WLAN we show that this method is easily adaptable to a variety of networking techn...

In recent work, Ishai, Prabhakaran and Sahai (CRYPTO 2008) presented a new compiler (hereafter the IPS compiler) for constructing protocols that are secure in the presence of malicious adversaries without an honest majority from protocols that are only secure in the presence of semi-honest adversaries. The IPS compiler has many important properties: it provides a radically different way of obta...

We introduce the notion of tamper-evidence for mix networks in order to defend against attacks aimed at covertly leaking secret information held by corrupted mix servers. This is achieved by letting observers (which need not be trusted) verify the absence of covert channels by means of techniques we introduce herein. Our tamper-evident mix network is a type of re-encryption mixnet in which a se...

Anomaly Detection Systems aim to construct accurate network traffic models with the objective to discover yet unknown malicious network traffic patterns. In this paper, we study the use of the same methods in order to create a covert channel which is not discovered by Anomaly Detection Systems and can be used to exfiltrate (malicous) traffic from a network. The channel is created by imitating c...

Hardware specialization in the form of accelerators offer significant improvement in performance and energy efficiency compared to general-purpose processors. However, there is usually a lack of security guarantees by the existing hardware design methodologies. In this report, we show that shared hardware accelerators are vulnerable to timing channel attacks and can leak sensitive information. ...

Covert timing channels provide a way to surreptitiously leak information from an entity in a higher-security level to an entity in a lower level. The difficulty of detecting or eliminating such channels makes them a desirable choice for adversaries that value stealth over throughput. When one considers the possibility of such channels transmitting information across network boundaries, the thre...

With the growing use of protocols obfuscation techniques, protocol identification for Q.O.S enforcement, traffic prohibition, and intrusion detection has became a complex task. This paper address this issue with a probabilistic identification analysis that combines multiples advanced identification techniques and returns an ordered list of probable protocols. It combines a payload analysis with...

For selling spectrum licenses economists have designed new auction types proceeding over several rounds and offering several licenses simultaneously. Communication between bidders usually is forbidden to prevent collusions (i.e., through separate compartments and supervision). We investigate these auctions from the cryptographic point of view and identify that the usual implementation by a succ...