go-raptorq implements the RaptorQ error correction code as defined in
RFC 6330. It includes a RFC-compliant encoder and decoder.
RaptorQ is a rateless erasure code (also known as fountain code), and provides two functions:
- Redundantly encoding a message into practically infinite number (~2**24) of symbols;
- Reliably decoding the original message from any subset of encoded symbols with high probability, provided that the cumulative size of the symbols received is equal to or slightly greater than the original message size.
RaptorQ is useful for a variety of purposes, including but not limited to:
- Transmitting a message reliably over a lossy and/or adversarial network path, without employing acknowledgement (feedback) mechanism or suffering from round-trip delays incurred thereby.
- Reliable object storage, where redundancy/fault-tolerence level—such as number of parity disks in RAID arrays—can be scaled up or down on demand without having to re-code contents on the existing disks.
We at Harmony are developing and using go-raptorq in order to implement a
near-optimal, adversary-resilient, and stable-latency message broadcasting
mechanism for use in our highly scalable and performant blockchain network.
To use go-raptorq in your Go application:
$ CGO_CXXFLAGS='-std=c++11' go get simple-rules/go-raptorq
go-raptorq has two main structs, Encoder and Decoder. One Encoder/Decoder
object is used to encode/decode one message. See the godoc (TODO) for
details.
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In addition to the terms and conditions of the license above, the licensee shall comply with the terms and conditions associated with all IETF IPR disclosure associated with RFC 6330. In no event shall the copyright owner or contributors be liable for damages arising in any way out of failure to comply with the terms and conditions of the above mentioned IPR disclosure.