Problem Statement
Summary:
The challenges of Content Routing in P2P networks are that:
- There is no central entity orchestrating the storage and discovery of content.
- There is no central directory to find how to reach every peer in the network.
- P2P networks present high node churn.Ā
- Thousands of peers and millions of content!
DRI: Anca Nitulescu
Agents:
- Content Providers (P),
- Content Consumers (C),
- Content Routers (R)
Roles:
- Providers store data (D) and make it available to consumers.
- Providers and consumers find each other through routers.
- Providers create advertisements called provider records (, which include content identifiersĀ ), and propagate them to the Routers.
- Consumers query the routers usingĀ , getting 0 or more corresponding provider records
Adding Privacy
Private Information Retrieval
Consumer queries Router while hiding the content she is after.
Avantages:
Leaks no info on the index
Drawbacks:
Does not scale well for Router computation and communication
Private Set Intersection
Consumer queries Router Content id
Router privately computes intersection between the queried content id and its record
Avantages:
Small Communication via FHE
Drawbacks:
Router may need to pre-process DB (expensive, not updatable)
Fully-Homomorphic Encryption
Provider encrypts its data.
The search function is evaluated over encrypted data.
Consumer gets the encrypted result.
Avantages:
Privacy from the encryption
No interaction
Drawbacks:
Not efficient in practice
Key management
Searchable Encryption
Data is encrypted under Consumerās key and delegated to the Router
Deterministic Encryption: exact match
Property-Preserving Encryption
Order-Preserving Encryption: range queries
Avantages:
Very efficient
Drawbacks:
Leaks repetitions
Some existing attacks to recover data
