1 / 13

Extended Attribute Based Encryption for Private Information Retrieval

Extended Attribute Based Encryption for Private Information Retrieval. 指導教授:鄭錦楸、郭文中 報告者 :許偉德 日期 : 2010/07/02. INTRODUCTION. 1. 2. PRELIMINARY. PERFORMANCE ANALYSIS. CONSTRUCTION. 3. 5. 3. 3. SECURITY AND PRIVACY EVALUATION. 6. 4. 4. 4. CONCLUSION. Outline. INTRODUCTION.

Download Presentation

Extended Attribute Based Encryption for Private Information Retrieval

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Extended Attribute Based Encryption for Private Information Retrieval 指導教授:鄭錦楸、郭文中 報告者 :許偉德 日期:2010/07/02

  2. INTRODUCTION 1 2 PRELIMINARY PERFORMANCE ANALYSIS CONSTRUCTION 3 5 3 3 SECURITY AND PRIVACY EVALUATION 6 4 4 4 CONCLUSION Outline

  3. INTRODUCTION • PIR enables the sensitivedata to be obtained only if the data authorizers allow the data receivers to access to the data. • ABE(attribute based encryption):a user is identified by a certain set of attributes, and ciphertext is encrypted under another set of attributes.

  4. Our Contribution. • EABE(Extended Attribute Based Encryption): • authorizers could authorize the data receiver separately by signing a signature. • Sender will encrypt the required data with the access structure and send the ciphertext to data receiver. • Only if the receiver gets enough authorizations which satisfy the access structure can he or she decrypts the ciphertext.

  5. IEABE(Improved EABE): • by using the ASPIR scheme • Each authorizer will generate an authorization on a requirement which includes the receiver identity, index of the data and some other policy. • The sender will also generate a ciphertext based on the requirement and the access structure. • Receiver could retrieve the data from the ciphertext obtained through ASPIR scheme if the access structure is satisfied.

  6. Sahai and Waters firstly proposed a attribute based encryption (ABE) scheme called fuzzy identity based encryption scheme in 2005. • Goyal, Pandey, Sahai and Waters further defined the concept of ABE:key-policy ABE (KPABE) and ciphertext-policy ABE(CPABE). • KPABE:which allows keys to be expressed by any monotonic formula over encrypted data. • CPABE:in standard model with the use of linear secret sharing scheme (LSSS) which is also expressive and efficient.

  7. PRELIMINARY • A. Access structure Definition 1 (Access Structure) • Let • The sets in r are called the authorized sets, and the sets not in r are called the unauthorized sets.

  8. B. Linear Secret Sharing Schemes Definition 2 (Linear Secret-Sharing Scheme (LSSS)). • A secret-sharing scheme II over a set of parities Ais called linear. • The shares for each party form a vector over Zp.

  9. C. Bilinear Maps Definition 3 (Bilinear Maps). • Let G and GTbe two multiplicative cyclic groups of prime order p.

  10. D. Decisional Bilinear Diffie-Hellman Assumption • When given the adversary must distinguish a valid tuple from a random element R in

  11. E. participants in our scheme • EABE and IEABE involve the initializer, a sender, a receiver, and authorizers, denoted by I, S, R and • I: generates a common parameter PK and then publishes PK authentically • S: has a data d which should be authorized by an authorized setA'in an access structure • Aigenerates their private/public key pair to sign message.

  12. In EABE,the ciphertext is generated according to the access structure • The authorization from Aigenerated according to the identity of R. • In IEABE,S and/or Rchoose a message mto be signed as a proof of authorization.

  13. Thank You !

More Related