1 research outputs found
Encapsulated Search Index: Public-Key, Sub-linear, Distributed, and Delegatable
We build the first sub-linear (in fact, potentially constant-time) public-key searchable encryption system:
β server can publish a public key .
β anybody can build an encrypted index for document under .
β client holding the index can obtain a token from the server to check if a keyword belongs to .
β search using is almost as fast (e.g., sub-linear) as the non-private search.
β server granting the token does not learn anything about the document , beyond the
keyword .
β yet, the token is specific to the pair : the client does not learn if other keywords belong to , or if w belongs to other, freshly indexed documents .
β server cannot fool the client by giving a wrong token .
We call such a primitive Encapsulated Search Index (ESI). Our ESI scheme can be made - distributed among servers in the best possible way: non-interactive, verifiable, and resilient to any coalition of up to malicious servers. We also introduce the notion of delegatable ESI and show how to extend our construction to this setting.
Our solution β including public indexing, sub-linear search, delegation, and distributed token generation β is deployed as a commercial application by Atakama