Net neutrality is the principle that Internet service providers must treat all data on the Internet the same, and not discriminate or charge differently by user, content, website, platform, application, type of attached equipment, or method of communication. For instance, under these principles, internet service providers are unable to intentionally block, slow down or charge money for specific websites and online content.
The term was coined by Columbia University media law professor Tim Wu in 2003, as an extension of the longstanding concept of a common carrier, which was used to describe the role of telephone systems.
A widely cited example of a violation of net neutrality principles was the Internet service provider Comcast's secret slowing  of uploads from peer-to-peer file sharing  applications by using forged packets. Comcast did not stop blocking these protocols, like BitTorrent, until the Federal Communications Commission ordered them to stop. In another minor example, The Madison River Communications company was fined US$15,000 by the FCC, in 2004, for restricting their customers' access to Vonage, which was rivaling their own services. AT&T was also caught limiting access to FaceTime, so only those users who paid for AT&T's new shared data plans could access the application. In July 2017, Verizon Wireless was accused of throttling after users noticed that videos played on Netflix and YouTube were slower than usual, though Verizon commented that it was conducting "network testing" and that net neutrality rules permit "reasonable network management practices".
Research suggests that a combination of policy instruments will help realize the range of valued political and economic objectives central to the network neutrality debate. Combined with strong public opinion, this has led some governments to regulate broadband Internet services as a public utility, similar to the way electricity, gas, and the water supply are regulated, along with limiting providers and regulating the options those providers can offer. In April of 2015, the FCC issued its Open Internet Order, which controversially reclassified Internet access - previously classified as an information service - as a common carrier telecommunications service; i.e. a public utility. But on December 14, 2017, the Commission, which was led by Chairman Ajit Pai, voted to partially repeal the 2015 Open Internet Order, classifying Internet access once again as an information service.
Definition and related principles
Internet neutrality
Network neutrality is the principle that all Internet traffic should be treated equally. Internet traffic includes all of the different messages, files and data sent over the Internet, including, for example, emails, digital audio files, digital video files, etc. According to Columbia Law School professor Tim Wu, the best way to explain network neutrality is that a public information network will end up being most useful if all content, websites, and platforms  are treated equally.
A more detailed proposed definition of technical and service network neutrality suggests that service network neutrality is the loyalty to the paradigm that operation of a service at a certain layer is not influenced by any data other than the data interpreted at that layer, and in accordance with the protocol specification for that layer.
Open Internet
Under an "open Internet" schema, the full resources of the Internet and means to operate on it should be easily accessible to all individuals, companies, and organizations.
Applicable concepts include: net neutrality, open standards, transparency, lack of Internet censorship, and low barriers to entry. The concept of the open Internet is sometimes expressed as an expectation of decentralized technological power, and is seen by some observers as closely related to open-source software, a type of software program whose maker allows users access to the code that runs the program, so that users can improve the software or fix bugs.
Proponents of net neutrality see this as an important component of an "open Internet", wherein policies such as equal treatment of data and open web standards allow those using the Internet to easily communicate, and conduct business and activities without interference from a third party.
In contrast, a "closed Internet" refers to the opposite situation, wherein established persons, corporations, or governments favor certain uses, restrict access to necessary web standards, artificially degrade some services, or explicitly filter out content. Some countries block certain websites or types of sites, and monitor and/or censor Internet use using Internet police, a specialized type of law enforcement, or secret police.
Dumb pipe
The concept of a "dumb network", comprising "dumb pipes", has been around since at least the early 1990s. The term "dumb network" refers to a network which is set up but has little or no control or management of the way users make use of the network. The term "dumb pipes" is analogous to water pipes used in a city water supply system; in theory, these pipes provide a steady supply of water to all users, regardless of the identity of the user or the users' activities with the water.
In a "dumb network", the endpoints are thought to be where the intelligence lies, and as such, proponents argue that the network should leave the management and operation of communications and data transfer to the end users, not a government bureau or Internet company. In 2013, the software company MetroTech Net, Inc.  coined the term "dumb wave", which is the 2010s-era application of the "dumb pipe" concept to the ubiquitous wireless network.
End-to-end principle
The end-to-end principle of network design was first laid out in the 1981 paper End-to-end arguments in system design by Jerome H. Saltzer, David P. Reed, and David D. Clark. The principle states that, whenever possible, communications protocol operations should be defined to occur at the end-points of a communications system, or as close as possible to the resources being controlled. According to the end-to-end principle, protocol features are only justified in the lower layers of a system if they are a performance optimization; hence, TCP retransmission for reliability is still justified, but efforts to improve TCP reliability should stop after peak performance has been reached.
They argued that reliable systems tend to require end-to-end processing to operate correctly, in addition to any processing in the intermediate system. They pointed out that most features in the lowest level of a communications system have costs for all higher-layer clients, even if those clients do not need the features, and are redundant if the clients have to re-implement the features on an end-to-end basis. This leads to the model of a minimal dumb network with smart terminals, a completely different model from the previous paradigm of the smart network with dumb terminals. Because the end-to-end principle is one of the central design principles of the Internet, and because the practical means for implementing data discrimination violate the end-to-end principle, the principle often enters discussions about net neutrality. The end-to-end principle is closely related, and sometimes seen as a direct precursor to the principle of net neutrality.
Traffic shaping
Traffic shaping is the control of computer network traffic to optimize or guarantee performance, improve latency, and/or increase usable bandwidth by delaying "packets" that meet certain criteria. In practice, traffic shaping is often accomplished by "throttling" certain types of data, such as streaming video or P2P file sharing. More specifically, traffic shaping is any action on a set of packets  which imposes additional delay on those packets such that they conform to some predetermined constraint . Traffic shaping provides a means to control the volume of traffic being sent into a network in a specified period, or the maximum rate at which the traffic is sent, or more complex criteria such as generic cell rate algorithm.
Over-provisioning
If the core of a network has more bandwidth than is permitted to enter at the edges, then good quality of service  can be obtained without policing or throttling. For example, landline telephone network employs admission control to limit user demand on the network core by refusing to create a circuit for the requested connection. During a natural disaster, for example, most users will get a busy signal if they pick up a landline phone, as the phone company prioritizes 9-1-1 and other emergency calls. Over-provisioning is a form of statistical multiplexing that makes liberal estimates of peak user demand. Over-provisioning is used in private networks such as WebEx and the Internet 2 Abilene Network, an American university network. David Isenberg believes that continued over-provisioning will always provide more capacity for less expense than QoS and deep packet inspection technologies.
By issue
Discrimination by protocol
Discrimination by protocol is the favoring or blocking information based on aspects of the communications protocol that the computers are using to communicate. In the US, a complaint was filed with the Federal Communications Commission against the cable provider Comcast alleging they had illegally inhibited users of its high-speed Internet service from using the popular file-sharing software BitTorrent. Comcast admitted no wrongdoing in its proposed settlement of up to 16 dollars per share in December 2009. However, a U.S. appeals court ruled in April 2010 that the FCC exceeded its authority when it sanctioned Comcast in 2008 for deliberately preventing some subscribers from using peer-to-peer file-sharing services to download large files. However, the FCC spokeswoman Jen Howard responded, "the court in no way disagreed with the importance of preserving a free and open Internet, nor did it close...