Previous research has demonstrated categorical perception (CP) of facial expressions from American Sign Language (ASL) in hearing, English-speaking non-signers. Notably, CP was observed even for faces with no obvious linguistic labels in English, suggesting the existence of covert categories based on nonlinguistic facial properties. However, in the earlier work, CP was assessed using memory pro...

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 t...

With the increasing growth of electronic communications, it is becoming important to provide a mechanism for enforcing various security policies on network communications. This paper discusses our implementation of several previously proposed protocols that enforce the Bell LaPadula security model. We also introduce a new protocol called \Quantized Pump" that ooers several advantages, and prese...

Effective choices generally require memory, yet little is known regarding the cognitive or neural mechanisms that allow memory to influence choices. We outline a new framework proposing that covert memory processing of hippocampus interacts with action-generation processing of prefrontal cortex in order to arrive at optimal, memory-guided choices. Covert, rapid action-memory simulation (CRAMS) ...

Covert channels are mechanisms for communicating information in ways that are difficult to detect. Data exfiltration can be an indication that a computer has been compromised by an attacker even when other intrusion detection schemes have failed to detect a successful attack. Covert timing channels use packet interarrival times, not header or payload embedded information, to encode covert messa...

Covert channels are used for information transmission in a manner that is not intended for communication and is difficult to detect. We propose a technique to prevent the information leakage via IP covert timing channels by inter-packet delays normalization in the process of packets sending. Recommendations for using the counteraction methods and choosing parameters were given. The advantage of...

In this letter, we consider the requirement of information freshness in covert communications for first time. With artificial noise (AN) generated from a full-duplex (FD) receiver, formulate covertness maximization problem under average age (AoI) constraint to optimize transmit probability signal. particular, not only represents generation rate signal but also prior alternative hypothesis commu...

The exploration of advanced covert timing channel design is important to understand and defend against covert timing channels. In this paper, we introduce a new class of covert timing channels, called model-based covert timing channels, which exploit the statistical properties of legitimate network traffic to evade detection in an effective manner. We design and implement an automated framework...

A network covert channel is created that operates by modulating the time between web resource accesses, with an “average web user” read-time used as a reference. While the covert channel may be classified as timing based, it does not operate by changing deterministic protocol attributes such as inter-packet delay, as do most timing based network covert channels. Instead, our channel communicate...