# UDPspeeder

A Tunnel which Improves your Network Quality on a High-latency Lossy Link by using Forward Error Correction.

When used alone, UDPspeeder improves only UDP connection. Nevertheless, if you used UDPspeeder + any UDP-based VPN together,
you can improve any traffic(include TCP/UDP/ICMP), currently OpenVPN/L2TP/ShadowVPN are confirmed to be supported。

![](/images/en/udpspeeder.PNG)

or

![image_vpn](/images/en/udpspeeder+openvpn3.PNG)

Assume your local network to your server is lossy. Just establish a VPN connection to your server with UDPspeeder + any UDP-based VPN, access your server via this VPN connection, then your connection quality will be significantly improved. With well-tuned parameters , you can easily reduce IP or UDP/ICMP packet-loss-rate to less than 0.01% . Besides reducing packet-loss-rate, UDPspeeder can also significantly improve your TCP latency and TCP single-thread download speed.

[UDPspeeder Wiki](https://github.com/wangyu-/UDPspeeder/wiki)

[简体中文](/doc/README.zh-cn.md)(内容更丰富)

# Efficacy
tested on a link with 100ms latency and 10% packet loss at both direction

### Ping Packet Loss
![](/images/en/ping_compare_mode1.png)

### SCP Copy Speed
![](/images/en/scp_compare2.PNG)

# Supported Platforms
Linux host (including desktop Linux,Android phone/tablet, OpenWRT router, or Raspberry PI).

For Windows and MacOS You can run UDPspeeder inside [this](https://github.com/wangyu-/udp2raw-tunnel/releases/download/20171108.0/lede-17.01.2-x86_virtual_machine_image.zip) 7.5mb virtual machine image.

# How does it work

UDPspeeder uses FEC(Forward Error Correction) to reduce packet loss rate, at the cost of addtional bandwidth. The algorithm for FEC is called Reed-Solomon.

![image0](/images/en/fec.PNG)

### Reed-Solomon

`
In coding theory, the Reed–Solomon code belongs to the class of non-binary cyclic error-correcting codes. The Reed–Solomon code is based on univariate polynomials over finite fields.
`

`
It is able to detect and correct multiple symbol errors. By adding t check symbols to the data, a Reed–Solomon code can detect any combination of up to t erroneous symbols, or correct up to ⌊t/2⌋ symbols. As an erasure code, it can correct up to t known erasures, or it can detect and correct combinations of errors and erasures. Reed–Solomon codes are also suitable as multiple-burst bit-error correcting codes, since a sequence of b + 1 consecutive bit errors can affect at most two symbols of size b. The choice of t is up to the designer of the code, and may be selected within wide limits.
`

![](/images/en/rs.png)

Check wikipedia for more info, https://en.wikipedia.org/wiki/Reed–Solomon_error_correction

# Getting Started

### Installing
Download binary release from https://github.com/wangyu-/UDPspeeder/releases

### Running (improves UDP traffic only)
Assume your server ip is 44.55.66.77, you have a service listening on udp port 7777.

```bash
# Run at server side:
./speederv2 -s -l0.0.0.0:4096 -r 127.0.0.1:7777  -f20:10 -k "passwd"

# Run at client side
./speederv2 -c -l0.0.0.0:3333  -r44.55.66.77:4096 -f20:10 -k "passwd"
```

Now connecting to UDP port 3333 at the client side is equivalent to connecting to port 7777 at the server side, and the connection has been boosted by UDPspeeder.

##### Note

`-f20:10` means sending 10 redundant packets for every 20 original packets.

`-k` enables simple XOR encryption

# Improves all traffic with OpenVPN + UDPspeeder

See [UDPspeeder + openvpn config guide](https://github.com/wangyu-/UDPspeeder/wiki/UDPspeeder-openvpn-config-guide).

# wiki
Check wiki for more info:

https://github.com/wangyu-/UDPspeeder/wiki

# Related repo

You can also try tinyfecVPN, a lightweight high-performance VPN with UDPspeeder's function built-in.

tinyfecVPN's repo:

https://github.com/wangyu-/tinyfecVPN

You can use udp2raw with UDPspeeder together to get better speed on some ISP with UDP QoS(UDP throttling).

udp2raw's repo：

https://github.com/wangyu-/udp2raw-tunnel