Small-scale UDP Fast Transmission Protocol
The SUFT (Small-scale UDP Fast Transmission) Protocol is an application layer transmission protocol based on UDP and implemented in Golang. It has lower latency than TCP and provides reliable and ordered delivery of a stream of octets under plain congestion control.
The protocol seeks for maximized throughput and minimizes impact of lost packets on throughput. It is only for small/medium-scale communication or some situations where TCP is not applicable.
e, err := suft.NewEndpoint(p *suft.Params) // for server conn := e.Listen() // or e.Accept() // for client conn, err := e.Dial(rAddr string) // your business ... conn.Close() e.Close()
scnt(sender: the count of unique data packets) and dups(sender: retransmission counter)
Lose Rate = dups/(scnt + dups)
Retransmit Rate = dups/scnt
latency, window and traffic speed
Speed = (1000 / latency) * mss * win
GPL version 3 or any later version
SUFT Protocol Copyright (C) 2016 spance, l2dy
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http:.
"suft-nc" package include a tool for testing, similar to netcat (nc).
go get -u -v github.com/spance/suft/examples/suft-nc
./suft-nc [-l addr:port] [-r addr:port] [-s] [-b 10] [-fr] < [send_file] > [recv_file]
-l: local bind address, e.g. localhost:9090 or :8080 -r: remote address (for client), e.g. 18.104.22.168:9090 or examples.com:8080 -b: max bandwidth of sending in mbps (be careful, see Notes#2) -s: for server -fr: enable fast retransmission (useful for lossy link) -ft: flat traffic (slow down bursty traffic, useful when sender has more bandwidth than receiver)
// send my_file to remote in 10mbps remote# ./suft-nc -l :9090 -s > recv_file local# ./suft-nc -r remote:9090 -b 10 -fr < my_file
// recv my_file from remote in 50mbps remote# ./suft-nc -l :9090 -s -b 50 -fr < my_file local# ./suft-nc -r remote:9090 > recv_file
// simple chat room remote# ./suft-nc -l :9090 -s local# ./suft-nc -r remote:9090
// remote, send 100MB stream in 50mbps (your bandwidth bottleneck) remote# dd if=/dev/zero bs=1M count=100 status=none | ./suft-nc -s -l :9090 -b 50 -fr -ft // status=none or status=noxfer
// local console#1, monitor traffic(for simplicity, we can use bmon) local# bmon -p eth0 // local console#2, recv stream local# ./suft-nc -r remote:9090 > /dev/null