1. Survey on Privacy-Related Technologies Presented by Richard Lin Zhou

2. Content Overview of technologies Communication based technologies Policy based technologies Application specific technologies

3. Privacy Related Technologies Privacy Protection Communication Based Mixed Zones k-anonymity based Policy BasedP3P, Confab Application Specific (privacy models) Hitckhike, etc.

4. Communication Based Approaches MIX Zone ◦ Mix zone vs Application zone ◦ Infrastructure based. k-anonymity: ◦ Basic principle: Make sure an user is not distinguishable from the other k-1 users in the same group. ANODOR: ◦ Anonymous On Demand Routing

5. MIX Zone Mix Zone: A connected spatial region of maximum size in which none of the users has registered any application callback. Application Zone: An area where a user has registered for a callback. A new identity is issued when entering a new application zone. No way to track a person if new ID is used each time Communication Based Approaches

6. k-anonymity based/related A user is k-anonymous if and only if he is indistinguishable from at least k-1 other users. Reduce the accuracy of disclosed location Most popular privacy technology under development ◦ Anonysense: k-anonymity by generalization ◦ VMDAV: k-anonymity by microaggregation ◦ Hybrid Methdologies Communication Based Approaches

7. k-anonymity based/related Anonysense ◦ Blurring mechanism by tessellation and clustering to protect privacy while reporting. ◦ k-anonymous report aggregation to improve the users’ privacy against applications receiving the context. Communication Based Approaches

8. k-anonymity based/related V-MDAV ◦ Blurring Mechanism by Micro-aggregation ◦ Creating sets of equivalence class with similar attributes. Domingo-Ferrer ◦ User select k-1 other users based on responses from peers. Hybrid V-MDAV ◦ Adaptively uses V-MDAV and Tessellation Communication Based Approaches

9. ANODR Anonymous On Demand Routing ◦ A routing protocol ◦ Make packets not traceable by any observing adversary. ◦ Routing scheme provides unlinkability. ◦ Impossible to judge a node is sending or just forwarding a packet Communication Based Approaches

10. Policy Based Approaches Let user be informed and in control of private information usage User must trust the system P3P ◦ Platform for Privacy Preference Project ◦ Encoding of Privacy Policies into XML ◦ Often impossible to enforce the human- readable policy

11. Policy Based Approaches Personal Location Privacy Policies ◦ Tools allowing individuals to adjust the accuracy for his location, identity, time, and speed. Confab ◦ Client centered architecture ◦ Data is sensed, stored and process on end- user’s devices, with better user-interface for sharing.

12. Application Specific Models Pseudonyms authentication for VANET (Vehicular Ad-hoc Networks) ◦ Enables vehicle on-board units to generate their own pseudonyms without affecting the system security while enhancing privacy protection.

13. Application Specific Models Privacy Risk Models ◦ Target for practical methods to create privacy sensitive applications. ◦ Help designer to create applications that provides end-users with a reasonable level of privacy protection that is relevant to the domain of application. ◦ A general method for refining privacy from an abstract concept into concrete application- specific issues.

14. Application Specific Models Hitchhiking – An example of Privacy Risk Models ◦ Targets for application that treat location as primary entity of interest (e.g. available tables in a coffee shop) ◦ Preserve the anonymity of reports without reducing the precision of location disclosures ◦ Location identifiers generated by client. No “trusted” servers. Can be application specific (e.g. Bus No. for bus tracing applications)

15. Conclusion Three main categories of approaches ◦ Communication/Information minimizing (reduction of data) ◦ Policy based approaches ◦ Application specific approaches (solve one problem at once)