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Title: Gaussian Multiuser Wiretap Channels in the Presence of a Jammer-Aided Eavesdropper
This paper considers secure communication in the presence of an eavesdropper and a malicious jammer. The jammer is assumed to be oblivious of the communication signals emitted by the legitimate transmitter(s) but can employ any jamming strategy subject to a given power constraint and shares her jamming signal with the eavesdropper. Four such models are considered: (i) the Gaussian point-to-point wiretap channel; (ii) the Gaussian multiple-access wiretap channel; (iii) the Gaussian broadcast wiretap channel; and (iv) the Gaussian symmetric interference wiretap channel. The use of pre-shared randomness between the legitimate users is not allowed in our models. Inner and outer bounds are derived for these four models. For (i), the secrecy capacity is obtained. For (ii) and (iv) under a degraded setup, the optimal secrecy sum-rate is characterized. Finally, for (iii), ranges of model parameter values for which the inner and outer bounds coincide are identified.  more » « less
Award ID(s):
2047913
NSF-PAR ID:
10397560
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Entropy
Volume:
24
Issue:
11
ISSN:
1099-4300
Page Range / eLocation ID:
1595
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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