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Covert Identification over �Binary-Input Discrete Memoryless Channels�

Qiaosheng (Eric) Zhang

Vincent Y. F. Tan

National University of Singapore

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Shannon’s Transmission Problem

Ahlswede & Dueck’s Identification Problem (1989)

Transmission vs Identification

Y/N

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Transmission vs Identification

	Throughput
Transmission
Identification [Ahlswede & Dueck’1989]

[Ahlswede & Dueck’1989]

[Han & Verdu’1992]

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Covert Identification

silent

active

Warden

Y/N

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Covert Identification

Weight constraints

No shared key required

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Most channel coding problems: Deterministic encoder

Identification problem: Stochastic encoder (each codeword is a distribution)

Why double-exponential

Enc

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Achievability

Block 1

Block 2

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Achievability

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Converse of identification problem relies on Channel Resolvability

Converse

Lemma. [Channel resolvability/Soft-covering Lemma]

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Consider any covert code,

Converse

Enc

Lemma. [Channel resolvability/Soft-covering Lemma]

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Consider any covert code,

Converse

Lemma. [Channel resolvability/Soft-covering Lemma]

Enc

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Consider any covert code,

Converse

Lemma. [Channel resolvability/Soft-covering Lemma]

Enc

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Converse

Enc

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THANK YOU

Reference

[Ahlswede-Dueck’89]: “Identification-via-channels”, IEEE Transactions on Information Theory 35.1 (1989): 15-29.
[Han-Verdu’92] : “New results in the theory of Identification via channels”, IEEE Transactions on Information Theory 38.1 (1992): 14-25.
[Bloch’16]: “Covert communication over noisy channels: A resolvability perspective ”, IEEE Transactions on Information Theory 62.5 (2016): 2334-2354.
[Bloch-Guha’17]: “Optimal covert communications using pulse position modulations ”, IEEE ISIT (2017).
[Wang et al.’16]: “Fundamental limits of communication with low probability of detection ”, IEEE Transactions on Information Theory 62.6 (2016): 3493-3503.