Do Not Forget the Past: A Buffer-Aided Framework for Relay Based Key Generation

다국어 초록 (Multilingual Abstract)

We address relay-assisted key generation whereintwo wireless nodes, that have no direct channel between them,seek the assistance of an intermediate relay to generate secretkeys. In a celebrated version of the relay-assisted protocol, asapplied by Lai et al., Zhou et al., Wang et al., and Waqas etal., the relay node generates pair-wise keys with the two nodes,and then broadcasts an XOR version of the two keys. Althoughsuch protocols are simple and effective, we observe that theyface reduction in key rates due to two problems. First, forconfidentiality, the relay broadcasts an XOR function of the pairwisekeys thereby pruning the length of the shared key to be theminimum of the key lengths of the pair-wise keys. Secondly, thebroadcast phase may also experience outages thereby not beingable to share the generated key in every round of the protocol.
Identifying these issues, we propose a buffer-aided relayingprotocol wherein buffer is used at the relay to store unusedsecret bits generated in the previous rounds of the protocol so asto provide confidentiality in the subsequent rounds of broadcast.
On this buffer-aided protocol, we propose a power-allocationstrategy between the phases of key generation and broadcast soas to maximize the throughput and key rate. Rigorous analysesshow that buffer-aided relay when implemented along with theproposed power-allocation strategy offer remarkable advantagesover existing baselines.

참고문헌 (Reference)

1 A. D. Wyner, "The common information of two dependent random variables" 21 (21): 163-179, 1975

2 M. Waqas, "Social-aware secret key generation for secure device-to-device communication via trusted and non-trusted relays" 17 (17): 3918-3930, 2018

3 P. Xu, "Simultaneously generating secret and private keys in a cooperative pairwiseindependent network" 11 (11): 1139-1150, 2016

4 M. Wilhelm, "Secure key generation in sensor networks based on frequency-selective channels" 31 (31): 1779-1790, 2013

5 H. Zhou, "Secret key generation in the two-way relay channel with active attackers" 9 (9): 476-488, 2014

6 R. Guillaume, "Secret key generation from static channels with untrusted relays" 2015

7 S. Nitinawarat, "Secret key generation for correlated Gaussian sources" 58 (58): 3373-3391, 2012

8 K. Ren, "Secret key generation exploiting channel characteristics in wireless communications" 18 (18): 6-12, 2011

9 U. M. Maurer, "Secret key agreement by public discussion from common information" 39 (39): 733-742, 1993

10 X. Tang, "Secrecy outage analysis of buffer-aided cooperative mimo relaying systems" 67 (67): 2035-2048, 2018

11 S. Mathur, "Radiotelepathy:Extracting a secret key from an unauthenticated wireless channel" 2008

12 C. D. T. Thai, "Physical-layer secret key generation with colluding untrusted relays" 15 (15): 1517-1530, 2016

13 T. Shimizu, "Physical-layer secret key agreement in two-way wireless relaying systems" 6 (6): 650-660, 2011

14 R. Nakai, "Physical layer security in buffer-statebased max-ratio relay selection exploiting broadcasting with cooperative beamforming and jamming" 14 (14): 431-444, 2019

15 Nasser Aldaghri, "Physical layer secret key generation in static environments" 15 : 2692-2705, 2020

16 Y. Sun, "On the monotonicity, log-concavity, and tight bounds of the generalized Marcum and Nuttall Q-functions" 56 (56): 1166-1186, 2010

17 A. Abdi, "On the estimation of the K parameter for the Rice fading distribution" 5 (5): 92-94, 2001

18 X. Liao, "On security-delay trade-offin two-hop wireless networks with buffer-aided relay selection" 17 (17): 1893-1906, 2018

19 M. W. Hirsch, "On algorithms for solving f(x)= 0" 32 (32): 281-312, 1979

20 H. M. Furqan, "New physical layer key generation dimensions : Subcarrier indices/positions-based key generation" 25 (25): 59-63, 2021

21 J. He, "Link selection for security-qos tradeoffs in buffer-aided relaying networks" 15 : 1347-1362, 2019

22 F. Benedetto, "LOS/NLOS detection by the normalized Rayleigh-ness test" 2009

23 C. Ye, "Information-theoretically secret key generation for fading wireless channels" 5 (5): 240-254, 2010

24 Y. L. Luke, "Inequalities for generalized hypergeometric functions" 5 (5): 41-65, 1972

25 H. Jagadeesh, "Group secret-key generation using algebraic rings in wireless networks" 70 (70): 1538-1553, 2021

26 T. M. Cover, "Elements of information theory" Wiley 1991

27 D. L. Hall, "Derivation of K-factor detection statistics to discriminate between LOS and NLOS scenarios" 2021

28 Q. Wang, "Cooperative secret key generation from phase estimation in narrowband fading channels" 30 (30): 1666-1674, 2012

29 L. Lai, "Cooperative key generation in wireless networks" 30 (30): 1578-1588, 2012

30 R. Ahlswede, "Common randomness in information theory and cryptography-Part I : Secret sharing" 39 (39): 1121-1132, 1993

31 I. Csiszar, "Common randomness and secret key generation with a helper" 46 (46): 344-366, 2000

32 R.Wilson, "Channel identification : Secret sharing using reciprocity in ultrawideband channels" 2 (2): 364-375, 2007

33 Y. Huang, "Channel frequency responsebased secret key generation in underwater acoustic systems" 15 (15): 5875-5888, 2016

34 Y. Polyanskiy, "Channel coding rate in the finite blocklength regime" 56 (56): 2307-2359, 2010

35 F. Rottenberg, "CSI-based versus RSS-based secret-key generation under correlated eavesdropping" 69 (69): 1868-1881, 2021

36 Jing Wan, "Buffer-aided two-hop secure communications with power control and link selection" 17 (17): 7635-7647, 2018

37 Jing Huang, "Buffer-aided relaying for twohop secure communication" 14 (14): 152-164, 2015

38 L. Lai, "A unified framework for key agreement over wireless fading channels" 7 (7): 480-490, 2012