Comparing Countermeasures against Interrupt-Related Covert Channels in an Information-Theoretic Framework

2007 ◽  
Author(s):  
Heiko Mantel ◽  
Henning Sudbrock
Keyword(s):  
Covert Channels ◽  
Information Theoretic

scholarly journals An Empirical Bandwidth Analysis of Interrupt-Related Covert Channels

2015 ◽  
Vol 6 (2) ◽  
pp. 1-22 ◽  
Author(s):  
Richard Gay ◽  
Heiko Mantel ◽  
Henning Sudbrock
Keyword(s):  
Empirical Evaluation ◽  
Network Interface ◽  
Theoretic Analysis ◽  
Covert Channels ◽  
Information Theoretic ◽  
Interface Card ◽  
Side Channels ◽  
Channel Bandwidth ◽  
Bandwidth Analysis

Interrupt-related covert channels (IRCCs) utilize hardware interrupts for enabling communication between processes. This article provides an empirical evaluation of IRCC vulnerabilities, based on an actual exploit. The evaluation combines experiments with an information-theoretic analysis for computing the channel bandwidth. The evaluation shows that a bandwidth of multiple bits per second is achievable in a desktop system via interrupts of a network interface card. This result clarifies the significance of this IRCC vulnerability for one particular system. The exploit presented is configurable, and the article provides a solution for computing an optimal exploit configuration for a given system. While side channels based on hardware interrupts have been discussed before, this is the first empirical evaluation of covert channels based on hardware interrupts.

Large-sample confidence intervals of information-theoretic measures in linguistics

2020 ◽  
Vol 6 (1) ◽  
pp. 19-54
Author(s):  
Ryan Ka Yau Lai ◽  
Youngah Do
Keyword(s):  
Maximum Likelihood ◽  
Corpus Linguistics ◽  
Delta Method ◽  
Confidence Bounds ◽  
Likelihood Estimator ◽  
Information Theoretic ◽  
Leibler Divergence ◽  
Information Theoretic Measures ◽  
Data Points ◽  
Measure Of Uncertainty

This article explores a method of creating confidence bounds for information-theoretic measures in linguistics, such as entropy, Kullback-Leibler Divergence (KLD), and mutual information. We show that a useful measure of uncertainty can be derived from simple statistical principles, namely the asymptotic distribution of the maximum likelihood estimator (MLE) and the delta method. Three case studies from phonology and corpus linguistics are used to demonstrate how to apply it and examine its robustness against common violations of its assumptions in linguistics, such as insufficient sample size and non-independence of data points.

Sign in / Sign up

Export Citation Format

Share Document