Broadcast Encryption Scheme Realizing Information Granularity by Tree Structure Source:Cryptology...
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Broadcast Encryption Scheme Realizing Information Granularity by Tree Structure Source: Cryptology and In formation Security Confere nce 2009 Author: 吳吳吳 吳吳吳吳 吳吳吳 、、 Speaker: 吳吳吳
Broadcast Encryption Scheme Realizing Information Granularity by Tree Structure Source:Cryptology and Information Security Conference 2009 Author: 吳宗成、林喬雯、林燕卿
Broadcast Encryption Scheme Realizing Information Granularity
by Tree Structure Source:Cryptology and Information Security
Conference 2009 Author: Speaker:
Slide 2
2 Outline /
Slide 3
3 (digital content) /
Slide 4
4 (1/5) (Information Granularity)
Slide 5
5 (2/5) (Tree-based Information Granularity)
Slide 6
6 (3/5) (Broadcast Encryption) session key CP
(Encryption)(Decryption) information (Encryption)(Decryption)
cipher block enabling block dk session key sk i UiUi
Slide 7
7 (4/5) CP: U i : ID i : Ui E: G: (base point) G O E O E E s cp
:CP X:CP l:CP M: m t M t=1,...,2 l -1
Slide 8
8 (5/5) No t : E m t (t=1,,f) L j : E (j=1,,l) lid j : j Lpk j
: j Lsk j : j u t : m t sk i : U i H: v E E k (): k D k (): k
Slide 9
9 (1/3) CP step 1. a, b GF (p) p E E y 2 = x 3 + ax + b mod p
a, b 4a 3 + 27b 2 0 (mod p) step 2. E G G G = O E O E E step 3. s
cp s cp Z p X = s cp G step 4. E R CP s cp R p G X
Slide 10
10 (2/3) step 1. M l 2 l -1 step 2. 1 2 root M 2 l -1 m t (t
=1,, 2 l -1) step 3. E m t No t E (t = 1,, f) mtmt m 2t m 2t+1
Slide 11
11 (2/3) step 4. E L j E (j= 1,, l) step 5. Lsk j Lpk j 1. lid
j Z p j=1,, l 2. j Lsk j E Q j Lsk j = lid j Q j 3. j Lpk j P j P j
+ Q j = R Lpk j =lid j P j +X Lpk j + Lsk j = lid j R + X CP lid j
Q j Lsk j No t (t= 1,, 2 l -1) L j (j = 1,, l) Lpk j
