Massively scalable multicast distribution solution
The library implements a unidirectional file delivery, without the need of a return channel.
This library implements the following RFCs
| RFC | Title | Link | | -------- | ---------- | -----------| | RFC 6726 | FLUTE - File Delivery over Unidirectional Transport | https://www.rfc-editor.org/rfc/rfc6726.html | | RFC 5775 | Asynchronous Layered Coding (ALC) Protocol Instantiation | https://www.rfc-editor.org/rfc/rfc5775.html | | RFC 5661 | Layered Coding Transport (LCT) Building Block | https://www.rfc-editor.org/rfc/rfc5651 | | RFC 5052 | Forward Error Correction (FEC) Building Block | https://www.rfc-editor.org/rfc/rfc5052 | | RFC 5510 | Reed-Solomon Forward Error Correction (FEC) Schemes | https://www.rfc-editor.org/rfc/rfc5510.html |
Transfer files over a UDP/IP network
```rust use flute::sender::Sender; use flute::sender::ObjectDesc; use flute::sender::Cenc; use std::net::UdpSocket; use std::time::SystemTime;
// Create UDP Socket let udpsocket = UdpSocket::bind("0.0.0.0:0").unwrap(); udpsocket.connect("224.0.0.1:3400").expect("Connection failed");
// Create FLUTE Sender let tsi = 1; let oti = Default::default(); let config = Default::default(); let mut sender = Sender::new(tsi, &oti, &config);
// Add object(s) (files) to the FLUTE sender let obj = ObjectDesc::createfrombuffer(b"hello world", "text/plain", &url::Url::parse("file:///hello.txt").unwrap(), 1, None, None, Cenc::Null, true, None, true).unwrap(); sender.add_object(obj);
// Always call publish after adding objects sender.publish(SystemTime::now());
// Send FLUTE packets over UDP/IP while let Some(pkt) = sender.read(SystemTime::now()) { udpsocket.send(&pkt).unwrap(); std::thread::sleep(std::time::Duration::frommillis(1)); }
```
Receive files from a UDP/IP network
```rust use flute::receiver::{writer, MultiReceiver, UDPEndpoint}; use std::net::UdpSocket; use std::time::SystemTime; use std::rc::Rc;
// Create UDP/IP socket to receive FLUTE pkt let endpoint = UDPEndpoint::new(None, "224.0.0.1".tostring(), 3400); let udpsocket = UdpSocket::bind(format!("{}:{}", endpoint.destinationgroupaddress, endpoint.port)).expect("Fail to bind");
// Create a writer able to write received files to the filesystem let writer = Rc::new(writer::ObjectWriterFSBuilder::new(&std::path::Path::new("./flutedir")) .unwraporelse(|| std::process::exit(0)));
// Create a multi-receiver capable of de-multiplexing several FLUTE sessions let mut receiver = MultiReceiver::new(writer, None, false);
// Receive pkt from UDP/IP socket and push it to the FLUTE receiver let mut buf = [0; 2048]; loop { let (n, src) = udpsocket.recv_from(&mut buf).expect("Failed to receive data"); let now = SystemTime::now(); receiver.push(&endpoint, &buf[..n], now).unwrap(); receiver.cleanup(now); } ```
The following error recovery algorithms are supported
The Oti module provides an implementation of the Object Transmission Information (OTI)
used to configure Forward Error Correction (FEC) encoding in the FLUTE protocol.
```rust use flute::sender::Oti; use flute::sender::Sender;
// Reed Solomon 2^8 with encoding blocks composed of // 60 source symbols and 4 repair symbols of 1424 bytes per symbol let oti = Oti::newreedsolomon_rs28(1424, 60, 4).unwrap(); let mut sender = Sender::new(1, &oti, &Default::default()); ```
The following schemes are supported during the transmission/reception
The FLUTE Sender is able to transfer multiple files in parallel by interleaving packets from each file. For example:
Pkt file1 -> Pkt file2 -> Pkt file3 -> Pkt file1 -> Pkt file2 -> Pkt file3 ...
The Sender can interleave blocks within a single file. The following example shows Encoding Symbols (ES) from different blocks (B) are interleaved. For example:
(B 1,ES 1)->(B 2,ES 1)->(B 3,ES 1)->(B 1,ES 2)->(B 2,ES 2)...
To configure the multiplexing, use the Config struct as follows:
```rust use flute::sender::Sender; use flute::sender::Config;
let config = Config { // Transfer a maximum of 3 files in parallel multiplexfiles: 3, // Interleave a maximum of 3 blocks within each file interleaveblocks: 3, ..Default::default() };
let mut sender = Sender::new(1, &Default::default(), &config);
```
bash
pip install flute-alc
Flute Sender python example
```python from flute import sender
# Flute Sender config parameters
sender_config = sender.Config()
# Object transmission parameters (no_code => no FEC)
# encoding symbol size : 1400 bytes
# Max source block length : 64 encoding symbols
oti = sender.Oti.new_no_code(1400, 64)
# Create FLUTE Sender
flute_sender = sender.Sender(1, oti, sender_config)
# Transfer a file
flute_sender.add_file("/path/to/file", 0, "application/octet-stream", None, None)
flute_sender.publish()
while True:
alc_pkt = flute_sender.read()
if alc_pkt == None:
break
#TODO Send alc_pkt over UDP/IP
```
Flute Receiver python example ```python from flute import receiver
# Write received objects to a destination folder
receiver_writer = receiver.ObjectWriterBuilder("/path/to/dest")
# FLUTE Receiver configuration parameters
receiver_config = receiver.Config()
tsi = 1
# Create a FLUTE receiver with the specified endpoint, tsi, writer, and configuration
udp_endpoint = receiver.UDPEndpoint("224.0.0.1", 1234)
flute_receiver = receiver.Receiver(udp_endpoint, tsi, receiver_writer, receiver_config)
while True:
# Receive LCT/ALC packet from UDP/IP multicast (Implement your own receive_from_udp_socket() function)
# Note: FLUTE does not handle the UDP/IP layer, you need to implement the socket reception mechanism yourself
pkt = receive_from_udp_socket()
# Push the received packet to the FLUTE receiver
flute_receiver.push(bytes(pkt))
```