nilRAG

Retrieval Augmented Generation (RAG) using Nillion's nilAI, nilDB, and nilQL. RAG is a technique that grants large language models information retrieval capabilities and context that they might be missing.

nilRAG combines multiparty computation (MPC) and trusted execution environment (TEE) technologies.

Overview

Data owners often possess valuable files that clients wish to query to enhance their LLM-based inferences. However, ensuring privacy is a key challenge: data owners want to keep their data confidential, and clients are equally concerned about safeguarding their queries.

nilRAG addresses this challenge by enabling secure data sharing and querying. It allows data owners to store their data securely in a nilDB cluster while allowing clients to query the data without exposing their queries or compromising the data's privacy.

The process involves leveraging a Trusted Execution Environment (TEE) server for secure computation through nilAI. Data owners upload their information to the nilDB cluster, while nilAI processes client queries and retrieves the most relevant results (top-k) without revealing sensitive information from either party.

Entities summary

Let us deep dive into the entities and their roles in the system.

1. Data Owners: Secure stores files for RAG Data owners contribute multiple files, where each file contains several paragraphs. Before sending the files to the nilDB instances, they are processed into N chunks of data and their corresponding embeddings:

   Chunks (ch_i): Represented as encoded strings.
   Embeddings (e_i): Represented as vectors of floats (fixed-point values).
   

   Once the files are encoded into chunks and embeddings, they are blinded before being uploaded to the NilDB, where each chunk and embedding is secret-shared.

2. Client: Issues a query q A client submits a query q to search against the data owners' files stored in NilDB and perform RAG (retrieve the most relevant data and use the top-k results for privacy-preserving machine learning (PPML) inference).

   Similar to the data encoding by data owners, the query is processed into its corresponding embeddings:

3. NilDB: Secure Storage and Query Handling NilDB stores the blinded chunks and embeddings provided by data owners. When a client submits a query, NilDB computes the differences between the query’s embeddings and each stored embedding in a privacy-preserving manner:

   differences = [embedding - query for embedding in embeddings]

   Key Points:

   • The number of differences (N) corresponds to the number of chunks uploaded by the data owners.
   • For secret-sharing-based NilDB, the computation is performed on the shares.

4. nilAI: Secure Processing and Retrieval The nilTEE performs the following steps:

   1. Retrieve and Reveal Differences: Connect to NilDB to fetch the blinded differences and then reveal the differences by reconstructing shares.

   2. Identify Top-k Indices: Sort the differences while retaining their indices to find the top_k matches:

      indexed_diff = list(enumerate(differences))
      sorted_indexed_diff = sorted(indexed_diff, key=lambda x: x[1])
      indices = [x[0] for x in sorted_indexed_diff]
      k = 5
      top_k_indices = indices[:k]

   3. Fetch Relevant Chunks: Request NilDB to retrieve the blinded chunks corresponding to the top_k_indices.

   4. Prepare for Inference: Combine the retrieved top_k_chunks with the original query. Use the data with an LLM inside the nilTEE for secure inference.

How to use

Installation

First install uv, then run:

# Create and activate virtual environment with uv
uv venv
source .venv/bin/activate

Then either follow the local installation:

# Install package in development mode
uv pip install -e .

or use pip:

pip install nilrag

Data owner

1. Initialization

If you would like to initialize your own schema, contact Nillion or open an issue in https://github.com/NillionNetwork/nilrag. You will be provided with:

1. schema: which is the structure of the data that the data owner will store. In this case we have embedding (vector<integer>) and chunk (string). Each data owner will upload multiple embeddings and chunk.
2. query: This is the nilDB query that will compute the differences under MPC between the stored data owner embeddings and the client's embedding.

2. Uploading Documents

After initialization, the data owner can upload their documents to the nilDB instance. We provide an example of how to do this in examples/data_owner_upload.py.

By running the script, the documents are uploaded to the nilDB instance in secret-shared form:

uv run examples/data_owner_upload.py

3. nilAI (TEE Server)

If you would like access to nilAI contact Nillion or open an issue in https://github.com/NillionNetwork/nilrag.

4. Client Query

After having nilDB initialized, documents uploaded, and access to nilAI, the client can query the nilDB instance. We provide an example of how to do this in examples/client_query.py.

By running the script, the client's query is sent to nilAI and the response is returned:

uv run examples/client_query.py

Running Tests

# Run a specific test file
uv run -m unittest test.rag