Open Source KCP Software

frp stands for exactly what it is: a fast reverse proxy. It helps you expose a local server behind a NAT or firewall to the Internet. It is currently under development, but already supports TCP and UDP, as well as HTTP and HTTPS protocols where requests can be forwarded to internal services by domain name. It also has a P2P connect mode and many other nifty features. These include configuration files, environment variables, a dashboard that shows you frp's status and proxies' statistics information, an Admin UI that helps you check and manage frpc's configuration, and many others.

A simple security tunnel written in Golang. Listening on multiple ports, multi-level forward proxies - proxy chain, standard HTTP/HTTPS/HTTP2/SOCKS4(A)/SOCKS5 proxy protocols support. Probing resistance support for web proxy, TLS encryption via negotiation support for SOCKS5 proxy. Support multiple tunnel types, tunnel UDP over TCP. Local/remote TCP/UDP port forwarding, TCP/UDP Transparent proxy, Shadowsocks Protocol (TCP/UDP), and SNI Proxy. Permission control, load balancing, route control, DNS resolver and proxy, and TUN/TAP Device. In GOST, GOST and other proxy services are considered as proxy nodes, GOST can handle the requests itself, or forward the requests to any one or more proxy nodes. In addition to configuring services directly from the command line, parameters can also be set by specifying the external configuration file with the -C parameter.

kcptun is a stable and secure tunnel based on KCP with N:M multiplexing and FEC. Available for ARM, MIPS, 386 and AMD64. kcptun is shipped with builtin packet encryption powered by various block encryption algorithms and works in Cipher Feedback Mode, for each packet to be sent, the encryption process will start from encrypting a nonce from the system entropy, so encryption to same plaintexts never leads to a same ciphertexts thereafter. kcptun made use of ReedSolomon-Codes to recover lost packets, which requires massive amount of computation, a low-end ARM device cannot satisfy kcptun well. To unleash the full potential of kcptun, a multi-core x86 homeserver CPU like AMD Opteron is recommended. If you insist on running under some ARM routers, you'd better turn off FEC and use salsa20 as the encryption method.

master is the active development branch and contains v2 code, for the stable v1 release (though it was once called v2.0), please refer to v1.0 branch. goflyway v2 is a special tool to forward local ports to a remote server securely, just like ssh -L. goflyway uses pure HTTP POST requests to relay TCP connections. There is no CONNECT involved nor needed because goflyway is designed mainly for those people who are behind a CONNECT-less HTTP proxy or want to accelerate connections through static CDNs. However pure HTTP requesting is definitely a waste of bandwidth if you already have a better network environment, so use -w to turn on WebSocket relay, or -K to turn on KCP relay if possible. In HTTP mode when the server received some data it can't just send them to the client directly because HTTP is not bi-directional, instead, the server must wait until the client requests them, which means these data will be stored in memory for some time.

GSnova is a high-performance proxy tool for bypassing internet censorship and securing network traffic through a range of supported transport protocols. It acts as a multi-protocol client/server proxy that can tunnel traffic over TLS, WebSocket, KCP, QUIC, and SSH. GSnova is optimized for resilience and speed under restrictive network conditions and supports multiple fronting strategies and obfuscation techniques. It's particularly suited for users in highly censored environments and developers building resilient networking tools.

Like libevent, libev, and libuv, libhv provides event loop with non-blocking IO and timer, but simpler api and richer protocols. Cross-platform (Linux, Windows, MacOS, BSD, Solaris, Android, iOS) High-performance EventLoop (IO, timer, idle, custom) TCP/UDP client/server/proxy. TCP supports heartbeat, reconnect, upstream, MultiThread-safe write and close, etc. Built-in common unpacking modes (FixedLength, Delimiter, LengthField) RUDP support: WITH_KCP. SSL/TLS support: (via WITH_OPENSSL or WITH_GNUTLS or WITH_MBEDTLS) HTTP client/server (support https http1/x http2 grpc). HTTP supports static service, indexof service, proxy service, sync/async API handler. HTTP supports RESTful, router, middleware, keep-alive, chunked, SSE, etc. WebSocket client/server.

KCP is a fast and reliable protocol that can achieve the transmission effect of a reduction of the average latency by 30% to 40% and reduction of the maximum delay by a factor of three, at the cost of 10% to 20% more bandwidth wasted than TCP. It is implemented by using the pure algorithm, and is not responsible for the sending and receiving of the underlying protocol (such as UDP), requiring the users to define their own transmission mode for the underlying data packet, and provide it to KCP in the way of callback. Even the clock needs to be passed in from the outside, without any internal system calls. The entire protocol has only two source files of ikcp.h, ikcp.c, which can be easily integrated into the user's own protocol stack. You may have implement a P2P, or a UDP-based protocol, but are lack of a set of perfect ARQ reliable protocol implementation, then by simply copying the two files to the existing project, and writing a couple of lines of code, you can use it.

Supported protocol: TCP, UDP, RUDP (Reliable UDP), RICMP (Reliable ICMP), RHTTP (Reliable HTTP), KCP, Quic. Support type: forward proxy, reverse agent, SOCKS5 forward agent, SOCKS5 reverse agent. Agreement and type can be freely combined. External agent agreement and internal forwarding protocols can freely combine. Support Shadowsocks plug-in, spp-shadowsocks-plugin, spp-shadowsocks-plugin-android.