Achievable rates for queue-based timing stegocodes

stegocodes;timing channel;steganography;mutual information;"shannons mappings"]

Ezzeddine, Ibtissam M. ; Moulin ; Pierre

关键词: stegocodes;    timing channel;    steganography;    mutual information;    "shannons mappings"];   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/15966/Ezzeddine_Ibtissam.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This work studies stegocodes (data-hiding codes) for covert communication over timing channels. In a timing channel, the information resides in the packet interdeparture times as opposed to the packets themselves. The en-coding procedure should preserve the statistics of the packet interarrival process. Our steganographic codes are based on two novel ideas, namely, queue-based codes and Shannon's encoding functions for channels with causal side information at the transmitter. The embedding of information bits is done by a Geo/Geo/1 queue servicing the interarrival times. Shannon's theory of coding with causal sideinformation at the transmitter is then used to study the queue-based stegocodes and their information-theoretic limits. Evaluating these limits for the Geo/Geo/1 queue is a formidable computational problem. An efficient computational approach is proposed to compute the maximum achievablerate of the queue-based stegocode and the optimal encoding functions. We also design simple practical codes, test them on a communication systemwhile taking network noise into account, and compare their performance to the mappings under study.