National Laboratory of Communication,UESTC 2017 Wireless relay Time slot 1: Time slot 2: Time slot 3: b1☐B2 Network Traffic Engineering
Network Traffic Engineering National Laboratory of Communication, UESTC 2017 Wireless relay Time slot 1: Time slot 2: Time slot 3: b1 b12 b2
National Laboratory of Communication,UESTC 2017 NC for Security Problem 1.Wired and wireless signals can be wiretapped. 2010f4力 20 Network Traffic Engineering
Network Traffic Engineering National Laboratory of Communication, UESTC 2017 20 NC for Security Problem 1. Wired and wireless signals can be wiretapped. 2010/4/1
National Laboratory of Communication,UESTC 2017 NC for Security A y Data packets are a and b. Let x and y be their linear M combinations,say, x=2a+3b,y=5a-4b y Receivers B and C know the secret coding coefficients 2,3,5,-4. x+y x+y B Figure adapted from Scienific American,Chinese 7/2007 edition Network Traffic Engineering
Network Traffic Engineering National Laboratory of Communication, UESTC 2017 21 NC for Security Data packets are a and b. Let x and y be their linear combinations, say, x = 2a+3b, y = 5a−4b x+y Receivers B and C know the secret coding coefficients 2, 3, 5, 4. x+y x+y Figure adapted from Scientific American, Chinese 7/2007 edition
National Laboratory of Communication,UESTC 2017 NC for Security Problem 1.Wired and wireless signals can be wiretapped. Problem 2.It might be inconvenient to update the secret codebook. Solution. original data random information original data zero mutual information between eavesdropped information 2010时4/1 Network Traffic Engineering
Network Traffic Engineering National Laboratory of Communication, UESTC 2017 22 NC for Security Problem 1. Wired and wireless signals can be wiretapped. Problem 2. It might be inconvenient to update the secret codebook. Solution. original data + random information zero mutual information between original data eavesdropped information 2010/4/1
National Laboratory of Communication,UESTC 2017 Secure NC Example by Yeung-Cail m message intended for m-x m+x the two nodes at bottom x=randomizer m-x m+x m-x X m+x Decode m(without any codebook) 2010f41 235 Network Traffic Engineering
Network Traffic Engineering National Laboratory of Communication, UESTC 2017 23 Secure NC [Example by Yeung-Cai] m = message intended for the two nodes at bottom x = randomizer m‐x m‐x m+x m+x m‐x x x x m+x Decode m (without any codebook) 2010/4/1