Named Data Networking (NDN) (related to content-centric networking (CCN), content-based networking, data-oriented networking or information-centric networking (ICN)) is a proposed Future Internet architecture inspired by years of empirical research into network usage and a growing awareness of unsolved problems in contemporary internet architectures like IP. NDN has its roots in an earlier project, Content-Centric Networking (CCN), which Van Jacobson first publicly presented in 2006. The NDN project is investigating Jacobson's proposed evolution from today's host-centric network architecture IP to a data-centric network architecture (NDN). The belief is that this conceptually simple shift will have far-reaching implications for how people design, develop, deploy, and use networks and applications.
NDN has three core concepts that distinguish NDN from other network architectures. First, applications name data and data names will directly be used in network packet forwarding; consumer applications request desired data by its name, so communications in NDN are consumer-driven. Second, NDN communications are secured in a data-centric manner, that is, each piece of data (called a Data packet) will be cryptographically signed by its producer and sensitive payload or name components can also be encrypted for the purpose of privacy; in this way, consumers can verify the packet regardless of how the packet is fetched. Third, NDN adopts a stateful forwarding plane where forwarders will keep a state for each data request (called an Interest packet) and erase the state when a corresponding Data packet comes back; NDN's stateful forwarding allows intelligent forwarding strategies and eliminates loops.
Its premise is that the Internet is primarily used as an information distribution network, which is not a good match for IP, and that the future Internet's "thin waist" should be based on named data rather than numerically addressed hosts. The underlying principle is that a communication network should allow a user to focus on the data they need, named content, rather than having to reference a specific, physical location where that data is to be retrieved from, named hosts. The motivation for this is derived from the fact that the vast majority of current Internet usage (a "high 90% level of traffic") consists of data being disseminated from a source to a number of users. Named-data networking comes with potential for a wide range of benefits such as content caching to reduce congestion and improve delivery speed, simpler configuration of network devices, and building security into the network at the data level.
Overview
Today's Internet's hourglass architecture centers on a universal network layer, IP, which implements the minimal functionality necessary for global inter-connectivity. The contemporary Internet architecture revolves around a host-based conversation model, created in the 1970s to allow geographically distributed users to use a few big, immobile computers. This thin waist enabled the Internet's explosive growth by allowing both lower and upper layer technologies to innovate independently. However, IP was designed to create a communication network, where packets named only communication endpoints.
Sustained growth in e-commerce, digital media, social networking, and smartphone applications has led to dominant use of the Internet as a distribution network. Distribution networks are more general than communication networks, and solving distribution problems via a point-to-point communication protocol is complex and error-prone.
The Named Data Networking (NDN) project proposed an evolution of the IP architecture that generalizes the role of this thin waist, such that packets can name objects other than communication endpoints. More specifically, NDN changes the semantics of network service from delivering the packet to a given destination address to fetching data identified by a given name. The name in an NDN packet can name anything – an endpoint, a data chunk in a movie or a book, a command to turn on some lights, etc. The hope is that this conceptually simple change allows NDN networks to apply almost all of the Internet's well-tested engineering properties to a broader range of problems beyond end-to-end communications. Examples of NDN applying lessons learned from 30 years of networking engineering are that self-regulation of network traffic (via flow balance between Interest (data request) and Data packets) and security primitives (via signatures on all named data) are integrated into the protocol from the start.