LibCamera is a complex camera support library for GNU+Linux, Android, and ChromeOS.

socat is a relay for bidirectional data transfer between two independent data channels---files, pipes, devices, sockets, etc. It can create "listening" sockets, named pipes, and pseudo terminals.

socat can be used, for instance, as TCP port forwarder, as a shell interface to UNIX sockets, IPv6 relay, for redirecting TCP oriented programs to a serial line, to logically connect serial lines on different computers, or to establish a relatively secure environment (su and chroot) for running client or server shell scripts with network connections.

This library allows controlling basic functions in SocketCAN from user-space. It requires a kernel built with SocketCAN support.

libnatpmp is a portable and asynchronous implementation of the Network Address Translation - Port Mapping Protocol (NAT-PMP) written in the C programming language.

sslh is a network protocol demultiplexer. It acts like a switchboard, accepting connections from clients on one port and forwarding them to different servers based on the contents of the first received data packet. Detection of common protocols like HTTP(S), SSL, SSH, OpenVPN, tinc, and XMPP is already implemented, but any other protocol that matches a regular expression can be added. sslh's name comes from its original application of serving both SSH and HTTPS on port 443, allowing SSH connections from inside corporate firewalls that block port 22.

Hashcash is a proof-of-work algorithm, which has been used as a denial-of-service countermeasure technique in a number of systems.

A hashcash stamp constitutes a proof-of-work which takes a parametrizable amount of work to compute for the sender. The recipient can verify received hashcash stamps efficiently.

This package contains a command-line tool for computing and verifying hashcash stamps.

Iodine tunnels IPv4 data through a DNS server. This can be useful in different situations where internet access is firewalled, but DNS queries are allowed. The bandwidth is asymmetrical, with limited upstream and up to 1 Mbit/s downstream.

Net::DNS::Resolver::Programmable is a programmable DNS resolver for offline emulation of DNS.

iwd is a wireless daemon for Linux that aims to replace WPA Supplicant. It optimizes resource utilization by not depending on any external libraries and instead utilizing features provided by the Linux kernel to the maximum extent possible.

Dropwatch is an interactive utility for monitoring and recording packets that are dropped by the kernel. It provides the commands dropwatch and dwdump.

Nanomsg is a socket library that provides several common communication patterns. It aims to make the networking layer fast, scalable, and easy to use. Implemented in C, it works on a wide range of operating systems with no further dependencies.

Danga::Socket is an abstract base class for objects backed by a socket which provides the basic framework for event-driven asynchronous IO, designed to be fast. Danga::Socket is both a base class for objects, and an event loop.

Libproxy handles the details of HTTP/HTTPS proxy configuration for applications across all scenarios. Applications using libproxy only have to specify which proxy to use.

YAZ is a C/C++ library for information retrieval applications using Z39.50, SRU or Solr Web Service protocols for information retrieval. It also offers ZOOM API implementing them.

Proxychains-ng is a preloader which hooks calls to sockets in dynamically linked programs and redirects them through one or more SOCKS or HTTP proxies.

The dhtnet is a C++ library providing abstractions for interacting with an OpenDHT distributed network.

IO::Socket::INET6 is an interface for AF_INET/AF_INET6 domain sockets in Perl.

PuTTY is a graphical text terminal client. It supports SSH, telnet, and raw socket connections with good terminal emulation. It can authenticate with public keys and Kerberos single-sign-on. It also includes command-line SFTP and older SCP implementations.

PageKite implements a tunneled reverse proxy which makes it easy to make a service (such as an HTTP or SSH server) on localhost visible to the wider Internet, even behind NAT or restrictive firewalls. A managed front-end relay service is available at https://pagekite.net/, or you can run your own.

RTMPdump is a toolkit for RTMP streams. All forms of RTMP are supported, including rtmp://, rtmpt://, rtmpe://, rtmpte://, and rtmps://.

Restbed is a comprehensive and consistent programming model for building applications that require seamless and secure communication over HTTP.

The THC IPv6 Toolkit provides command-line tools and a library for researching IPv6 implementations and deployments. It requires Linux 2.6 or newer and only works on Ethernet network interfaces.

ENet's purpose is to provide a relatively thin, simple and robust network communication layer on top of UDP. The primary feature it provides is optional reliable, in-order delivery of packets. ENet omits certain higher level networking features such as authentication, server discovery, encryption, or other similar tasks that are particularly application specific so that the library remains flexible, portable, and easily embeddable.

Wireshark is a network protocol analyzer, or packet sniffer, that lets you capture and interactively browse the contents of network frames.