Capacity follows the links
Faster links become ready for more data sooner and therefore carry more. The distribution changes as link conditions change.
One connection, many links
Use it like a socket from Rust
The TCP transport discovers routes between the two hosts and uses each as a link.
Both ends receive a stream implementing AsyncRead and
AsyncWrite.
use aggligator_transport_tcp::simple::tcp_connect;
use tokio::io::AsyncWriteExt;
// Connect to "server" over all network interfaces.
let mut stream = tcp_connect(["server"], 5900).await?;
stream.write_all(b"hello").await?;use aggligator_transport_tcp::simple::tcp_listen;
// Listen on all network interfaces.
let listener = tcp_listen("[::]:5900".parse()?).await?;
loop {
// One connection, including all its links.
let mut stream = listener.accept().await?;
}
A Connector combines different transport types in the same connection.
This client can reach a device over the network and over USB at once.
let mut connector = Connector::new();
connector.add(TcpConnector::new(["server"], 5900).await?);
connector.add(UsbConnector::new(|dev, _| dev.vendor_id() == 0x1209)?);
let stream = connector.channel().unwrap().await?.into_stream();Use Aggligator with existing TCP applications
The agg-tunnel utility carries ordinary TCP connections over
Aggligator. Existing clients and servers can use aggregated links without changes
to their code.
Features
Connection survives network changes
Links may fail, return, be added or be removed while the connection runs. When none remain, transport connectors keep reconnecting for a configurable time instead of immediately closing the logical connection.
Bring your own links
Aggligator does its link aggregation in user space, over ordinary ordered byte streams or packet streams, without multipath support from the operating system or network.
Authenticated link attachment
A secret established with Diffie-Hellman protects the connection identifier used when adding links. Payload data is not encrypted; use TLS for untrusted links.
Per-link statistics
Each link reports latency, throughput and unacknowledged data. Applications can consume the values directly or display them with the terminal monitor.
Safe Rust on native and WebAssembly
Aggligator contains no unsafe code, runs on Tokio and supports
native platforms and WebAssembly.
Adapts to unequal links
Simple packet striping can let one slow link hold back an otherwise fast connection. Aggligator instead adjusts how much data is in flight on each link while the connection runs.
Send on the next ready link
Aggligator does not calculate a fixed bandwidth share. A faster link finishes sending sooner, becomes ready again and naturally carries more packets.
Limit links that delay delivery
Acknowledgements show how much received data is waiting behind an earlier packet. If that backlog grows, the sender reduces the unacknowledged-data allowance for the link used by the oldest outstanding packet.
Retest links set aside
When faster alternatives exist, a link with excessive round-trip time can be removed from normal scheduling. Test data and a ping periodically check whether it is ready to return.
Links of every kind
Transport crates create links for Aggligator. A connection can combine different transport types.
| Carries links over | Crate |
|---|---|
| TCP | aggligator-transport-tcp |
| WebSockets | aggligator-transport-websocket |
| WebSockets from a browser | aggligator-transport-websocket-web |
| USB | aggligator-transport-usb |
| WebUSB from a browser | aggligator-transport-webusb |
| Bluetooth on Linux | aggligator-transport-bluer |
| SOCKS5 proxies | aggligator-transport-socks |
| Anything above, wrapped in TLS | aggligator-wrapper-tls |
Common uses
How to bond internet connections and keep them alive when the network changes.
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Combine multiple internet connections
How Aggligator splits a connection across multiple uplinks, including which workloads benefit.
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Keep connections alive while
switching networks
How a logical connection survives a device moving between Wi-Fi and mobile data.