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  • - or simply channel refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel in telecommunications and computer networking. A channel is used to convey an information signal, for example a digital bit stream, from one or several senders (or transmitters) to one or several receivers. A channel has a certain capacity for transmitting information, often measured by its bandwidth in Hz or its data rate in bits per second. Communicating data from one location to another requires some form of pathway or medium. These pathways, called communication channels, use two types of media: cable (twisted-pair wire, cable, and fiber-optic cable) and broadcast (microwave, satellite, radio, and infrared).

  • - a network communication mode in telecommunications and computer networking, where a communication session or a semi-permanent connection is established before any useful data can be transferred, and where a stream of data is delivered in the same order as it was sent. The alternative to connection-oriented transmission is connectionless communication, for example the datagram mode communication used by the IP and UDP protocols, where data may be delivered out of order, since different packets are routed independently, and may be delivered over different paths.

  • - often referred to as CL-mode communication, is a data transmission method used in packet switching networks in which each data unit is individually addressed and routed based on information carried in each unit, rather than in the setup information of a prearranged, fixed data channel as in connection-oriented communication. Under connectionless communication between two network end points, a message can be sent from one end point to another without prior arrangement. The device at one end of the communication transmits data addressed to the other, without first ensuring that the recipient is available and ready to receive the data. Some protocols allow for error correction by requested retransmission. Internet Protocol (IP) and User Datagram Protocol (UDP) are connectionless protocols.

  • - also called path addressing, allows a sender of a packet to partially or completely specify the route the packet takes through the network. In contrast, in conventional routing, routers in the network determine the path incrementally based on the packet's destination. Another routing alternative, label switching, is used in connection-oriented networks such as X.25, frame relay, ATM and MPLS.


to sort

  • Beej's Guide to Network Programming - how-to guide on network programming using Internet sockets, or "sockets programming", for those of you who prefer it. The sockets API, though started by the Berkeley folk, has been ported to many many platforms, including Unix, Linux, and even Windows.Unfortunately, it can be a little, um, "much" to digest the API, but as long as you know some C or C++, this guide should springboard you into the realm of network programming with hopefully as little hassle as humanly possible!

  • High Performance Browser Networking (O'Reilly) - Performance is a feature. This book provides a hands-on overview of what every web developer needs to know about the various types of networks (WiFi, 3G/4G), transport protocols (UDP, TCP, and TLS), application protocols (HTTP/1.1, HTTP/2), and APIs available in the browser (XHR, WebSocket, WebRTC, and more) to deliver the best—fast, reliable, and resilient—user experience.

  • Netbox - solution for modeling and documenting modern networks. By combining the traditional disciplines of IP address management (IPAM) and datacenter infrastructure management (DCIM) with powerful APIs and extensions, NetBox provides the ideal "source of truth" to power network automation. Available as open source software under the Apache 2.0 license, NetBox serves as the cornerstone for network automation in thousands of organizations.

  • - or epidemic protocol is a procedure or process of computer peer-to-peer communication that is based on the way epidemics spread. Some distributed systems use peer-to-peer gossip to ensure that data is disseminated to all members of a group. Some ad-hoc networks have no central registry and the only way to spread common data is to rely on each member to pass it along to their neighbors.




  • - a bottom-up, citizenship-driven technological, social and economic project with the objective of creating a free, open and neutral telecommunications network based on a commons model. The development of this common-pool infrastructure eases the access to quality, fair-priced telecommunications in general and broadband Internet connections in particular, for everybody. Moreover, it generates a model for collaborative economic activity based on proximity and sustainability.


  • - also known as a forwarding table or MAC table, is most commonly used in network bridging, routing, and similar functions to find the proper interface to which the input interface should forward a packet. It is a dynamic table that maps MAC addresses to ports. It is the essential mechanism that separates network switches from network hubs. Content-addressable memory (CAM) is typically used to efficiently implement the FIB, thus it is sometimes called a CAM table.


Home router

  • LEDE project is founded as a spin-off of the OpenWrt project and shares many of the same goals. We are building an embedded Linux distribution that makes it easy for developers, system administrators or other Linux enthusiasts to build and customize software for embedded devices, especially wireless routers. The name LEDE stands for Linux Embedded Development Environment. [6]


  • Quagga is a routing software suite, providing implementations of OSPFv2, OSPFv3, RIP v1 and v2, RIPng and BGP-4 for Unix platforms, particularly FreeBSD, Linux, Solaris and NetBSD. Quagga is a fork of GNU Zebra.



See Comms, Security#Firewalls etc.

  • Network protocols, sans I/O - provides a single location for people to reference when looking for network protocol implementations written in Python that perform no I/O (this means libraries that operate directly on text or bytes; this excludes libraries that just abstract out I/O).

Network configuration

Goes a little something like;

options rotate



  show (and temp. set) network routes avaliable. in /sbin, in root $PATH only
route -n
  show network routes available, just ip


ip a
  # list network devices and their status

ip link set [interface] up
  # start a network interface

ip route add default via dev eth0

  • veth - Virtual Ethernet Devices. They can act as tunnels between network namespaces to create a bridge to a physical network device in another namespace, but can also be used as standalone network devices.

  • - used to dump socket statistics. It allows showing information similar to netstat. It can display more TCP and state informations than other tools.
  • - netstat maintains a static table of metrics entries, while nstat parses the whole /proc files. Since netstat is obsolete, new entries are not taken into account. netstat appears more user-friendly by describing some metrics with plain English, while nstat displays raw information. This can be considered as an advantage to roughly identify the purpose of the metric, but also a drawback if you are interested in the RFC name of the variable, going through netstat source code is hence a mandatory step. Parsing nstat output is also easier, even almost done thanks to the JSON output format option.

Network management

  • systemd-networkd - a system service that manages networks. It detects and configures network devices as they appear, as well as creating virtual network devices. To configure low-level link settings independently of networks, see systemd-networkd will create network devices based on the configuration in systemd.netdev(5) files, respecting the [Match] sections in those files. systemd-networkd will manage network addresses and routes for any link for which it finds a .network file with an appropriate [Match] section, see For those links, it will flush existing network addresses and routes when bringing up the device. Any links not matched by one of the .network files will be ignored. It is also possible to explicitly tell systemd-networkd to ignore a link by using Unmanaged=yes option, see

  • - The main network file must have the extension .network; other extensions are ignored. Networks are applied to links whenever the links appear. The .network files are read from the files located in the system network directory /usr/lib/systemd/network, the volatile runtime network directory /run/systemd/network and the local administration network directory /etc/systemd/network. All configuration files are collectively sorted and processed in lexical order, regardless of the directories in which they live. However, files with identical filenames replace each other. Files in /etc have the highest priority, files in /run take precedence over files with the same name in /usr/lib. This can be used to override a system-supplied configuration file with a local file if needed. As a special case, an empty file (file size 0) or symlink with the same name pointing to /dev/null disables the configuration file entirely (it is "masked").

  • - A standalone dialog-based script to select a wifi network from a list. Similar to wifi-menu found in Arch Linux, but uses systemd-networkd and wpa_supplicant instead of netctl.


From Arch Linux devs, profile based


Generally for embedded systems.

Network Manager


Traffic control


Netfilter / iptables

  • - a framework provided by the Linux kernel that allows various networking-related operations to be implemented in the form of customized handlers. Netfilter offers various functions and operations for packet filtering, network address translation, and port translation, which provide the functionality required for directing packets through a network, as well as for providing ability to prohibit packets from reaching sensitive locations within a computer network. Netfilter represents a set of hooks inside the Linux kernel, allowing specific kernel modules to register callback functions with the kernel's networking stack. Those functions, usually applied to the traffic in form of filtering and modification rules, are called for every packet that traverses the respective hook within the networking stack.
  • - a user-space application program that allows a system administrator to configure the tables provided by the Linux kernel firewall (implemented as different Netfilter modules) and the chains and rules it stores. Different kernel modules and programs are currently used for different protocols; iptables applies to IPv4, ip6tables to IPv6, arptables to ARP, and ebtables to Ethernet frames.
iptables -F
  # flush rules

  # accept policy for output chain traffic
iptables -P INPUT DROP
  # drop policy for input chain traffic
iptables -P FORWARD DROP
  # drop policy for forward chain traffic

iptables -A INPUT --in-interface lo -j ACCEPT
  • YouTube: Mastering IPTables, Part I - Linux Journal Presents: Linux comes with a powerful firewall built-in, although the interface can be a little intimidating. This is the first in a multi-part tutorial on how to master basic and not-so-basic IPTables functionality and create the perfect firewall for your home network.

  • husk - a natural language wrapper around the Linux iptables packet filtering engine (iptables). It is designed to abstract the sometimes confusing syntax of iptables, allowing use of rules that have better readability, and expressed in a more 'freeform' fashion compared to normal 'raw' iptables rules. husk can be used on either firewall/router computers (with multiple network interfaces), or standalone systems (with one network interface). Each interface (real or virtual) is called a 'zone' in husk. Zones are given a friendly name which is what is used in the rule definitions. This abstracts the Linux device names (eg, eth0, ppp0, bond0 etc) into much more intuitive names such as NET, LAN and DMZ. This has the added benefit of moving interfaces in the future can be done simply by changing the name-to-device mapping.

  • ebtables - a filtering tool for a Linux-based bridging firewall. It enables transparent filtering of network traffic passing through a Linux bridge. The filtering possibilities are limited to link layer filtering and some basic filtering on higher network layers. Advanced logging, MAC DNAT/SNAT and brouter facilities are also included.The ebtables tool can be combined with the other Linux filtering tools (iptables, ip6tables and arptables) to make a bridging firewall that is also capable of filtering these higher network layers. This is enabled through the bridge-netfilter architecture which is a part of the standard Linux kernel.The ebtables and arptables codebase is maintained by the netfilter developers, who were so kind to take over maintenance of the software. This website is kept mainly as a documentation reference.


  • - a subsystem of the Linux kernel providing filtering and classification of network packets/datagrams/frames. It has been available since Linux kernel 3.13 released on 19 January, 2014. nftables is supposed to replace netfilter. Both subsystems have been co-authored by Patrick McHardy. Among the advantages of nftables over netfilter is less code duplication and more throughput. nftables is configured via the user-space utility nft while netfilter is configured via the utilities iptables, ip6tables, arptables and ebtables frameworks. nftables utilizes the building blocks of the Netfilter infrastructure, such as the existing hooks into the networking stack, connection tracking system, userspace queueing component, and logging subsystem.

  • NCD - scripting language for network configuration and much more

  • Horde is linux-based networking middleware that allows an application to stripe data from multiple streams across a set of dissimilar wireless network channels. Horde's approach aims to decrease the programming costs associated with building complex mobile systems that use network striping.


  • linuximq - Pseudo-driver for the intermediate queue device. (IMQ) The imq device has two common usage cases: Ingress shaping: With linux only egress shaping is possible (except for the ingress queue which can only do rate limiting). IMQ enables you to use egress qdiscs for real ingress shaping. Shaping over multiple interfaces: Qdiscs get attached to devices. A consequence of this is that one qdisc can only handle traffic going to the interface it is attached to. Sometimes it is desireable to have global limits on multiple interfaces. With IMQ you can use iptables to specify which packets the qdiscs sees, so global limits can be placed.



  • - (internet service daemon) is a super-server daemon on many Unix systems that provides Internet services. For each configured service, it listens for requests from connecting clients. Requests are served by spawning a process which runs the appropriate executable, but simple services such as echo are served by inetd itself. External executables, which are run on request, can be single- or multi-threaded. First appearing in 4.3BSD, it is generally located at /usr/sbin/inetd. Often called a super-server, inetd listens on designated ports used by Internet services such as FTP, POP3, and telnet. When a TCP packet or UDP packet arrives with a particular destination port number, inetd launches the appropriate server program to handle the connection. For services that are not expected to run with high loads, this method uses memory more efficiently, since the specific servers run only when needed. Furthermore, no network code is required in the service-specific programs, as inetd hooks the sockets directly to stdin, stdout and stderr of the spawned process. For protocols that have frequent traffic, such as HTTP and POP3, a dedicated server that intercepts the traffic directly may be preferable.

  • - whenever a request for service arrives, the inetd daemon is tricked into running the tcpd program instead of the desired server. tcpd logs the request and does some additional checks. When all is well, tcpd runs the appropriate server program and goes away.



In systemd, three target units take the role of $network: has very little meaning during start-up. It only indicates that the network management stack is up after it has been reached. Whether any network interfaces are already configured when it is reached is undefined. It's primary purpose is for ordering things properly at shutdown: since the shutdown ordering of units in systemd is the reverse of the startup ordering, any unit that is ordered can be sure that it is stopped before the network is shut down if the system is powered off. This allows services to cleanly terminate connections before going down, instead of abruptly losing connectivity for ongoing connections, leaving them in an undefined state. Note that is a passive unit: you cannot start it directly and it is not pulled in by any services that want to make use of the network. Instead, it is pulled in by the network management service itself. Services using the network should hence simply place an dependency in their unit files, and avoid any or even is a target that actively waits until the nework is "up", where the definition of "up" is defined by the network management software. Usually it indicates a configured, routable IP address of some kind. It's primary purpose is to actively delay activation of services until the network is set up. It is an active target, meaning that is may be pulled in by the services requiring the network to be up, but is not pulled in by the network management service itself. By default all remote mounts defined in /etc/fstab pull this service in, in order to make sure the network is up before it is attempted to connect to a network share. Note that normally, if no service requires it, and if not remote mount point is configured this target is not pulled into the boot, thus avoiding any delays during boot should the network not be available. It is strongly recommended not to pull in this target too liberally: for example network server software should generally not pull this in (since server software generally is happy to accept local connections even before any routable network interface is up), it's primary purpose is network client software that cannot operate without network. is a target that may be used to order services before any network interface is configured. It's primary purpose is for usage with firewall services that want to establish a firewall before any network interface is up. It's a passive unit: you cannot start it directly and it is not pulled in by the the network management service, but by the service that wants to run before it. Network management services hence should set, but avoid any or even Services that want to be run before the network is configured should place and also set to pull it in. This way, unless there's actually a service that needs to be ordered before the network is up the target is not pulled in, hence avoiding any unnecessary synchronization point.


to resort

sudo lsof -i
  ports open

sudo netstat -plnt

ss -tnlp

sudo nmap -sT -O localhost

nc 123 < /dev/null; echo $?
  test local port, 1 for closed 0 for open

  advanced traceroute + ping


  • netcat - a versatile tool that is able to read and write data across TCP and UDP network . Combined with other tools and redirection it can be used in number of ways in your scripts. You will be surprised to see what you can accomplish with Linux netcat command.
nc -l 8888
  listen on port 8888

nc server1 8888
  connect to port 8888


  • Ncat - a feature-packed networking utility which reads and writes data across networks from the command line. Ncat was written for the Nmap Project as a much-improved reimplementation of the venerable Netcat. It uses both TCP and UDP for communication and is designed to be a reliable back-end tool to instantly provide network connectivity to other applications and users. Ncat will not only work with IPv4 and IPv6 but provides the user with a virtually limitless number of potential uses.


  • socat - a relay for bidirectional data transfer between two independent data channels. Each of these data channels may be a file, pipe, device (serial line etc. or a pseudo terminal), a socket (UNIX, IP4, IP6 - raw, UDP, TCP), an SSL socket, proxy CONNECT connection, a file descriptor (stdin etc.), the GNU line editor (readline), a program, or a combination of two of these. These modes include generation of "listening" sockets, named pipes, and pseudo terminals.
socat -d -d TCP-L:22,reuseaddr,fork SYSTEM:"nc \$SOCAT_PEERADDR 22"
  # Confuse people SSHing to your host with a redirect back to theirs.
hostA$ tar c mydir | lzop | socat - tcp-listen:1234
hostB$ socat tcp:hostA:1234 | lzop -d | tar x


  • Guidedog - an advanced routing/network configuration utility for KDE 3 and 4 running on Linux 2.4 & 2.6 based machines. Using Guidedog you can easily activate packet routing/forwarding and also more advanced networking such as IP masquerade and Port Forwarding.



  • Scapy - a powerful interactive packet manipulation program. It is able to forge or decode packets of a wide number of protocols, send them on the wire, capture them, match requests and replies, and much more. It can easily handle most classical tasks like scanning, tracerouting, probing, unit tests, attacks or network discovery (it can replace hping, 85% of nmap, arpspoof, arp-sk, arping, tcpdump, tethereal, p0f, etc.). It also performs very well at a lot of other specific tasks that most other tools can't handle, like sending invalid frames, injecting your own 802.11 frames, combining technics (VLAN hopping+ARP cache poisoning, VOIP decoding on WEP encrypted channel, ...), etc.


  • BitMeter OS - a free, open-source, bandwidth monitor that works on Windows, Linux and Mac OSX. BitMeter OS keeps track of how much you use your internet/network connection, and allows you to view this information either via a web browser, or by using the command line tools.The Web Interface displays various graphs and charts that show how your internet/network connection has been used over time.

to sort

  • Upside-Down-Ternet - My neighbours are stealing my wireless internet access. I could encrypt it or alternately I could have fun.

  • - a high performance, small footprint Captive Portal, offering by default a simple splash page restricted Internet connection, yet incorporates an API that allows the creation of sophisticated authentication applications.


  • netsniff-ng toolkit - a free Linux networking toolkit, a Swiss army knife for your daily Linux network plumbing if you will. Its gain of performance is reached by zero-copy mechanisms, so that on packet reception and transmission the kernel does not need to copy packets from kernel space to user space and vice versa. Our toolkit can be used for network development and analysis, debugging, auditing or network reconnaissance.

The netsniff-ng toolkit consists of the following utilities:

  • netsniff-ng, a fast zero-copy analyzer, pcap capturing and replaying tool
  • trafgen, a multithreaded low-level zero-copy network packet generator
  • mausezahn, high-level packet generator for HW/SW appliances with Cisco-CLI
  • bpfc, a Berkeley Packet Filter compiler, Linux BPF JIT disassembler
  • ifpps, a top-like kernel networking statistics tool
  • flowtop, a top-like netfilter connection tracking tool
  • curvetun, a lightweight curve25519-based IP tunnel
  • astraceroute, an autonomous system (AS) trace route utility




  • - a tcpdump like tool for eXpress Data Path (XDP). It can capture packets and actions / return codes from XDP programs, using standard tcpdump / libpcap filter expressions.






  • iPerf - a The TCP, UDP and SCTP network active bandwidth measurement tool. It supports tuning of various parameters related to timing, buffers and protocols (TCP, UDP, SCTP with IPv4 and IPv6). For each test it reports the bandwidth, loss, and other parameters. This is a new implementation that shares no code with the original iPerf and also is not backwards compatible. iPerf was orginally developed by NLANR/DAST. iPerf3 is principally developed by ESnet / Lawrence Berkeley National Laboratory. It is released under a three-clause BSD license.


  • Netperf - a benchmark that can be used to measure the performance of many different types of networking. It provides tests for both unidirecitonal throughput, and end-to-end latency. The environments currently measureable by netperf include: TCP and UDP via BSD Sockets for both IPv4 and IPv6, DLPI, Unix Domain Sockets, SCTP for both IPv4 and IPv6


  • NetHogs - a small 'net top' tool. Instead of breaking the traffic down per protocol or per subnet, like most tools do, it groups bandwidth by process. NetHogs does not rely on a special kernel module to be loaded. If there's suddenly a lot of network traffic, you can fire up NetHogs and immediately see which PID is causing this. This makes it easy to indentify programs that have gone wild and are suddenly taking up your bandwidth.


  • nload - a console application which monitors network traffic and bandwidth usage in real time. It visualizes the in- and outgoing traffic using two graphs and provides additional info like total amount of transfered data and min/max network usage.



  • bwm-ng - Bandwidth Monitor NG, is a small and simple console-based live network and disk io bandwidth monitor for Linux, BSD, Solaris, Mac OS X and others.


  • tcptrack - a packet sniffer, which passively watches for connections on a specified network interface, tracks their states, and lists them in a manner similar to the Unix 'top' command. It displays source and destination addresses and ports, connection state, idle time, and bandwidth usage.


  • Ostinato - an open-source, cross-platform network packet crafter/traffic generator and analyzer with a friendly GUI. Craft and send packets of several streams with different protocols at different rates. For the full feature list see below. Ostinato aims to be "Wireshark in Reverse" and become complementary to Wireshark.


  • EtherApe is a graphical network monitor for Unix modeled after etherman. Featuring link layer, IP and TCP modes, it displays network activity graphically. Hosts and links change in size with traffic. Color coded protocols display.


  • hping is a command-line oriented TCP/IP packet assembler/analyzer. The interface is inspired to the ping(8) unix command, but hping isn't only able to send ICMP echo requests. It supports TCP, UDP, ICMP and RAW-IP protocols, has a traceroute mode, the ability to send files between a covered channel, and many other features.


  • ngrep strives to provide most of GNU grep's common features, applying them to the network layer. ngrep is a pcap-aware tool that will allow you to specify extended regular or hexadecimal expressions to match against data payloads of packets. It currently recognizes IPv4/6, TCP, UDP, ICMPv4/6, IGMP and Raw across Ethernet, PPP, SLIP, FDDI, Token Ring and null interfaces, and understands BPF filter logic in the same fashion as more common packet sniffing tools, such as tcpdump and snoop.


  • Cacti is a complete network graphing solution designed to harness the power of RRDTool's data storage and graphing functionality. Cacti provides a fast poller, advanced graph templating, multiple data acquisition methods, and user management features out of the box. All of this is wrapped in an intuitive, easy to use interface that makes sense for LAN-sized installations up to complex networks with hundreds of devices.



  • SmokePing - keeps track of your network latency. Best of breed latency visualisation. Interactive graph explorer. Wide range of latency measurement plugins. Master/Slave System for distributed measurement. Highly configurable alerting system. Live Latency Charts with the most 'interesting' graphs. Free and OpenSource Software written in Perl written by Tobi Oetiker, the creator of MRTG and RRDtool


  • Bro - a passive, open-source network traffic analyzer. It is primarily a security monitor that inspects all traffic on a link in depth for signs of suspicious activity. More generally, however, Bro supports a wide range of traffic analysis tasks even outside of the security domain, including performance measurements and helping with trouble-shooting. [17]


  • Wireshark - the world's foremost network protocol analyzer. It lets you see what's happening on your network at a microscopic level. It is the de facto (and often de jure) standard across many industries and educational institutions.

  • tshark - The Wireshark Network Analyzer


  • iftop - does for network usage what top does for CPU usage. It listens to network traffic on a named interface and displays a table of current bandwidth usage by pairs of hosts. Handy for answering the question "why is our ADSL link so slow?".



  • - a small 'net top' tool. Instead of breaking the traffic down per protocol or per subnet, like most tools do, it groups bandwidth by process. NetHogs does not rely on a special kernel module to be loaded. If there's suddenly a lot of network traffic, you can fire up NetHogs and immediately see which PID is causing this. This makes it easy to identify programs that have gone wild and are suddenly taking up your bandwidth. Since NetHogs heavily relies on /proc, most features are only available on Linux. NetHogs can be built on Mac OS X and FreeBSD, but it will only show connections, not processes.


  • vnStat - a console-based network traffic monitor for Linux and BSD that keeps a log of network traffic for the selected interface(s). It uses the network interface statistics provided by the kernel as information source. This means that vnStat won't actually be sniffing any traffic and also ensures light use of system resources. However, in Linux at least a 2.2 series kernel is required.


  • NTM - a monitor of the network and internet traffic for Linux.



  • IPTraf - a console-based network statistics utility for Linux. It gathers a variety of figures such as TCP connection packet and byte counts, interface statistics and activity indicators, TCP/UDP traffic breakdowns, and LAN station packet and byte counts.


  • bettercap - Swiss army knife for network attacks and monitoring.





See also DNS

  • - a set of technologies that automatically creates a usable computer network based on the Internet Protocol Suite (TCP/IP) when computers or network peripherals are interconnected. It does not require manual operator intervention or special configuration servers. Without zeroconf, a network administrator must set up network services, such as Dynamic Host Configuration Protocol (DHCP) and Domain Name System (DNS), or configure each computer's network settings manually. Zeroconf is built on three core technologies: automatic assignment of numeric network addresses for networked devices, automatic distribution and resolution of computer hostnames, and automatic location of network services, such as printing devices.

  • avahi - mDNS/DNS-SD - a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. This enables you to plug your laptop or computer into a network and instantly be able to view other people who you can chat with, find printers to print to or find files being shared. Compatible technology is found in Apple MacOS X (branded "Bonjour" and sometimes "Zeroconf"). Avahi is primarily targetted at Linux systems and ships by default in most distributions. It is not ported to Windows at this stage, but will run on many other BSD-like systems. The primary API is D-Bus and is required for usage of most of Avahi, however services can be published using an XML service definition placed in /etc/avahi/services.See also the nss-mdns project, which allows hostname lookup of *.local hostnames via mDNS in all system programs using nsswitch

Mix network

  • - are routing protocols that create hard-to-trace communications by using a chain of proxy servers known as mixes[2] which take in messages from multiple senders, shuffle them, and send them back out in random order to the next destination (possibly another mix node). This breaks the link between the source of the request and the destination, making it harder for eavesdroppers to trace end-to-end communications. Furthermore, mixes only know the node that it immediately received the message from, and the immediate destination to send the shuffled messages to, making the network resistant to malicious mix nodes.

Loopix / MixNet

Simulation / emulation

  • OMNeT++ is an extensible, modular, component-based C++ simulation library and framework, primarily for building network simulators. "Network" is meant in a broader sense that includes wired and wireless communication networks, on-chip networks, queueing networks, and so on. Domain-specific functionality such as support for sensor networks, wireless ad-hoc networks, Internet protocols, performance modeling, photonic networks, etc., is provided by model frameworks, developed as independent projects. OMNeT++ offers an Eclipse-based IDE, a graphical runtime environment, and a host of other tools. There are extensions for real-time simulation, network emulation, alternative programming languages (Java, C#), database integration, SystemC integration, and several other functions.

  • Netkit - an environment for setting up and performing networking experiments at low cost and with little effort. It allows to "create" several virtual network devices (full-fledged routers, switches, computers, etc.) that can be easily interconnected in order to form a network on a single PC. Networking equipments are virtual but feature many of the characteristics of the real ones, including the configuration interface.

  • Marionnet - a virtual network laboratory: it allows users to define, configure and run complex computer networks without any need for physical setup. Only a single, possibly even non-networked GNU/Linux host machine is required to simulate a whole Ethernet network complete with computers, routers, hubs, switches, cables, and more. Support is also provided for integrating the virtual network with the physical host network. Marionnet was born in April 2005 as a simple textual interface to Netkit, itself based on User Mode Linux.

  • EVE-NG: Community Edition - clientless multivendor network emulation software that empowers network and security professionals with huge opportunities in the networking world.

  • SIPp - a free Open Source test tool / traffic generator for the SIP protocol. It includes a few basic SipStone user agent scenarios (UAC and UAS) and establishes and releases multiple calls with the INVITE and BYE methods. It can also reads custom XML scenario files describing from very simple to complex call flows. It features the dynamic display of statistics about running tests (call rate, round trip delay, and message statistics), periodic CSV statistics dumps, TCP and UDP over multiple sockets or multiplexed with retransmission management and dynamically adjustable call rates.Other advanced features include support of IPv6, TLS, SCTP, SIP authentication, conditional scenarios, UDP retransmissions, error robustness (call timeout, protocol defense), call specific variable, Posix regular expression to extract and re-inject any protocol fields, custom actions (log, system command exec, call stop) on message receive, field injection from external CSV file to emulate live users.SIPp can also send media (RTP) traffic through RTP echo and RTP / pcap replay. Media can be audio or video.While optimized for traffic, stress and performance testing, SIPp can be used to run one single call and exit, providing a passed/failed verdict.

  • SeagulL - a free, Open Source (GPL) multi-protocol traffic generator test tool. Primarily aimed at IMS (3GPP, TISPAN, CableLabs) protocols (and thus being the perfect complement to SIPp for IMS testing), Seagull is a powerful traffic generator for functional, load, endurance, stress and performance/benchmark tests for almost any kind of protocol.In addition, its openness allows to add the support of a brand new protocol in less than 2 hours - with no programming knowledge. For that, Seagull comes with several protocol families embedded in the source code: Binary/TLV (Diameter, Radius and many 3GPP and IETF protocols) External library (TCAP, SCTP) Text (XCAP, HTTP, H248 ASCII)

Software-defined networking

See also Virtualisation, IaaS

  • Maestro is an "operating system" for orchestrating network control applications. Maestro provides interfaces for implementing modular network control applications to access and modify state of the network, and coordinate their interactions. Maestro is a platform for achieving automatic and programmatic network control functions using these modularized applications. Although this project focuses on building an OpenFlow controller using Maestro, Maestro is not only limited to OpenFlow networks.


See Security


  • Reticulum Network - the cryptography-based networking stack for building local and wide-area networks with readily available hardware. It can operate even with very high latency and extremely low bandwidth. Reticulum allows you to build wide-area networks with off-the-shelf tools, and offers end-to-end encryption and connectivity, initiator anonymity, autoconfiguring cryptographically backed multi-hop transport, efficient addressing, unforgeable delivery acknowledgements and more.

The vision of Reticulum is to allow anyone to be their own network operator, and to make it cheap and easy to cover vast areas with a myriad of independent, inter-connectable and autonomous networks. Reticulum is not one network. It is a tool for building thousands of networks. Networks without kill-switches, surveillance, censorship and control. Networks that can freely interoperate, associate and disassociate with each other, and require no central oversight. Networks for human beings. Networks for the people.

Reticulum is a complete networking stack, and does not rely on IP or higher layers, but it is possible to use IP as the underlying carrier for Reticulum. It is therefore trivial to tunnel Reticulum over the Internet or private IP networks. Having no dependencies on traditional networking stacks frees up overhead that has been used to implement a networking stack built directly on cryptographic principles, allowing resilience and stable functionality, even in open and trustless networks. No kernel modules or drivers are required. Reticulum runs completely in userland, and can run on practically any system that runs Python 3.

  • I made the prepper version of the Internet : preppers - Since 2014, I have been trying to solve the problem of being able to build reliable communications networks in the case of mass failure of existing infrastructure. A lot of fragmented solutions and limited tools exist, but in reality, what was really missing was a complete communications stack designed for use by normal people without centralised coordination of any kind. A sort of "Internet Protocol for the people" if you will. A system that would allow anyone to easily build secure and resilient long-range networks with simple, available tools. Systems that would work and allow secure and private comms even when SHTF. So in 2014 I set out to do build that system. Well, it's been a while, and while it is by no means perfect, the Reticulum Network Stack now exists, and it does exactly that. It allows you to build networks over LoRa or Packet Radio, WiFi or fiber optics (or anything actually), and to connect those networks together.


  • - a command-line utility written in Python that facilitates shell sessions over Reticulum networks and aims to provide a similar experience to SSH.


  • - LXMF is a simple and flexible messaging format and delivery protocol that allows a wide variety of implementations, while using as little bandwidth as possible. It is built on top of Reticulum and offers zero-conf message routing, end-to-end encryption and Forward Secrecy, and can be transported over any kind of medium that Reticulum supports. LXMF is efficient enough that it can deliver messages over extremely low-bandwidth systems such as packet radio or LoRa. Encrypted LXMF messages can also be encoded as QR-codes or text-based URIs, allowing completely analog paper message transport.


  • - you to build private and resilient communications platforms that are in complete control and ownership of the people that use them. No signups, no agreements, no handover of any data, no permissions and gatekeepers. Nomad Network is build on LXMF and Reticulum, which together provides the cryptographic mesh functionality and peer-to-peer message routing that Nomad Network relies on. This foundation also makes it possible to use the program over a very wide variety of communication mediums, from packet radio to fiber optics. Nomad Network does not need any connections to the public internet to work. In fact, it doesn't even need an IP or Ethernet network. You can use it entirely over packet radio, LoRa or even serial lines. But if you wish, you can bridge islanded networks over the Internet or private ethernet networks, or you can build networks running completely over the Internet. The choice is yours.


  • - an LXMF client for Android, Linux and macOS. It allows you to communicate with other people or LXMF-compatible systems over Reticulum networks using LoRa, Packet Radio, WiFi, I2P, Encrypted QR Paper Messages, or anything else Reticulum supports.

Project V / V2Ray / Vmess

  • Project V - a set of tools to help you build your own privacy network over internet. The core of Project V, named V2Ray, is responsible for network protocols and communications. It can work alone, as well as combine with other tools. This website is mainly a manual for V2Ray, with some additional information regarding the whole project.
  • Multiple inbound/outbound proxies: one V2Ray instance supports in parallel multiple inbound and outbound protocols. Each protocol works independently.
  • Customizable routing: incoming traffic can be sent to different outbounds based on routing configuration. It is easy to route traffic by target region or domain.
  • Multiple protocols: V2Ray supports multiple protocols, including Socks, HTTP, Shadowsocks, VMess etc. Each protocol may have its own transport, such as TCP, mKCP, WebSocket etc.
  • Obfuscation: V2Ray has built in obfuscation to hide traffic in TLS, and can run in parallel with web servers.
  • Reverse proxy: General support of reverse proxy. Can be used to build tunnels to localhost.
  • Multiple platforms: V2Ray runs natively on Windows, Mac OS, Linux, etc. There is also third party support on mobile.

  • mKCP - a reliable stream transport. It is an UDP based protocol. mKCP sends more traffic for lower latency. To transfer the same amount of data, mKCP usually requires more throughput than TCP does.

Project X

  • Project X - Fear not the clouds that obscure the view, golden eyes like a torch brighten the sky
  • High-speed protocol: Original VLESS and XTLS protocols, free from redundant encryption, release CPU power
  • Free combination: Perfect fallback mechanism, effectively prevent active detection, multi-service sharing ports
  • Ultra-low occupancy: OpenWRT RaspberryPi and other simplified devices can be used
  • Powerful routing: Highly customizable routing system to meet various usage requirements and fully exploit network performance
  • Full compatibility: Fully compatible with v2ray-core configuration files and API calls
  • Affinity: Active community discussions and contributions, MPL 2.0 open source license

  • VLESS | Project X - a stateless lightweight transport protocol, which is divided into inbound and outbound parts, and can be used as a bridge between Xray clients and servers. Unlike VMess, VLESS does not rely on system time, and the authentication method is also UUID.

  • X-UI - multi-user Xray graphical management panel (replacing V2-UI and V2Ray). - provides a graphical user interface for managing servers and users. You can visually build servers for Shadowsocks, V2ray, Xray, Trojan, and other popular protocols. You can also monitor VPS performance and traffic usage in real time. X-UI replaces the older V2-UI panel.


See Mesh


Wireless broadband


to sort

View The Daily Show, etc. in the UK, etc. Mofity HTTP headers; X-Forwarded-For "" [22]

  • GLIF, the Global Lambda Integrated Facility, is an international consortium that promotes the paradigm of lambda networking.

  • OpenSignalMaps - database of cell phone towers, cell phone signal strength readings, and Wi-Fi access points around the world

  • Pi-hole -  Network-wide ad blocking via your own Linux hardware

  • - lens stands for "live editing of network streams"lens is a framework that allows you to tap live cabling for inspection and injection.