Index

An encrypted index organizes vectors for secure search. Index data is always encrypted; the server computes similarity without accessing plaintext vectors.

Properties

• Encryption: Cipher-only for index storage.

• Query Modes: Plaintext (faster) or Ciphertext (private).

• Similarity: Inner Product (IP).

• Dimension: 32-4096 (max 4096).

Mental Model

Think of an index like a table in an RDBMS:

• Each "row" is a vector, and it can have associated metadata (e.g., ID, title, URI).

• All vectors in the same index share the same fixed dimension (analogous to a fixed schema).

• You can insert rows, query for similar rows, and remove the whole table when done.

Lifecycle

Guidance

• Choose the dimension to match your embedding model.

• Prefer ciphertext queries when privacy is paramount.

• Unload rarely used indexes to conserve memory.

• Implement robust error handling for production.