iroh-sync

Multi-dimensional key-value documents with an efficient synchronization protocol.

The crate operates on Replicas. A replica contains an unlimited number of Entries. Each entry is identified by a key, its author, and the replica's namespace. Its value is the 32-byte BLAKE3 hash of the entry's content data, the size of this content data, and a timestamp. The content data itself is not stored or transferred through a replica.

All entries in a replica are signed with two keypairs:

• The Namespace key, as a token of write capability. The public key is the NamespaceId, which also serves as the unique identifier for a replica.
• The Author key, as a proof of authorship. Any number of authors may be created, and their semantic meaning is application-specific. The public key of an author is the [AuthorId].

Replicas can be synchronized between peers by exchanging messages. The synchronization algorithm is based on a technique called range-based set reconciliation, based on this paper by Aljoscha Meyer:

Range-based set reconciliation is a simple approach to efficiently compute the union of two sets over a network, based on recursively partitioning the sets and comparing fingerprints of the partitions to probabilistically detect whether a partition requires further work.

The crate exposes a generic storage interface with in-memory and persistent, file-based implementations. The latter makes use of redb, an embedded key-value store, and persists the whole store with all replicas to a single file.

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.