1. Privacy Preserving Ranked Multi-Keyword
Search for Multiple Data Owners in Cloud
Computing
Source : IEEE Transactions on Computers , 2015
Authors :Wei Zhang, Yaping Lin, Sheng Xiao, Die Wu, Siwang Zhou
Speaker : Pengxu Tian
Date: 2017/09/21
In this paper, authors proposed a new authentication scheme for heterogeneous WSN. Therefore, I will introduce heterogeneous WSN later.

2. Outline Introduction Proposed scheme Performance analysis
This is my outline
First, I will introduce what is heterogeneous WSN. And then is Proposed scheme.

3. Introduction Background of Searchable Encryption: Cloud computing
Security concern

4. Introduction Basic system model for Searchable Encryption Data Owner
Data Users

5. Introduction
Preliminary
Bilinear map:

6. Proposed scheme(1/9) System model of this paper (3) (5) (6) (4) (2)
(7)
(5)
(1)
(6)
(2)
(4)

7. Proposed scheme(2/9) Notation Description The trapdoor for 𝑇 𝑊 Oi
A data owner Fi
The plaintext file collection of Oi Ci
The ciphertext file collection of Fi W
The keyword collection
𝑊 𝑖
Oi’s encrypted keyword collection of W 𝑊
The subset of W which represents queried keywords
𝑇 𝑊
The trapdoor for 𝑇 𝑊
𝑆 𝑖,𝑗,𝑡
The relevance score of tth keyword to jth file of ith data owner

8. Proposed scheme(3/9)
Data user authentication

9. Proposed scheme(4/9) Keyword encryption 𝑆 𝑎 = 𝑔 𝑘 𝑎1 ⋅ 𝑘 𝑎2 ⋅ 𝑟 𝑎
𝑆 𝑎 = 𝑔 𝑘 𝑎1 ⋅ 𝑘 𝑎2 ⋅ 𝑟 𝑎
Data Owner
Administration server
Cloud server

10. Proposed scheme(5/9) Trapdoor generation 𝑆 𝑎 = 𝑔 𝑘 𝑎1 ⋅ 𝑘 𝑎2 ⋅ 𝑟 𝑎
𝑆 𝑎 = 𝑔 𝑘 𝑎1 ⋅ 𝑘 𝑎2 ⋅ 𝑟 𝑎
Data user
Administration server
Cloud server

11. Proposed scheme(6/9)
Match algorithm

12. Proposed scheme(7/9)
Ranked search

13. Proposed scheme(8/9) Ranking search results For the same data owner
For different data owners
𝑇 𝑗,2 𝐻 𝑖 𝑖

14. Proposed scheme(9/9)
Ranking search results

15. Performance analysis
identity or password bytes, nonce 16 bytes, timestamp 19 bytes, hash value 20 bytes, symmetric key 16 bytes

16. Performance analysis
identity or password bytes, nonce 16 bytes, timestamp 19 bytes, hash value 20 bytes, symmetric key 16 bytes

17. Thanks for attention