NDN

Named Data Networking (NDN) is a research framework for the future Internet that emphasizes data itself rather than host locations. It is a leading architecture within the Information-Centric Networking (ICN) paradigm, which seeks to simplify data access, improve security, and support mobility by focusing on named content rather than addresses.

NDN operates with two core packet types: Interest packets, which request a piece of data by its name, and Data packets, which carry the named content plus a cryptographic signature. Consumers issue Interests; routers forward them toward potential sources, and Data packets follow the reverse path back to the requester.

Routers maintain three data structures: a Content Store (in-network cache) for cached Data, a Pending Interest Table (PIT) for outstanding Interests, and a Forwarding Information Base (FIB) for name-based routing. When a Data packet is cached, it may satisfy pending Interests; if not, the Interest is forwarded according to FIB. Upon Data arrival, routers forward it toward all faces with matching PIT entries and cache the content for future requests.

Security in NDN is data-centric. Data packets are signed by the producer, enabling verifiable authenticity regardless of the delivery path or intermediaries. This design supports fine-grained trust models and data integrity, while allowing encryption to be applied at the application layer as needed.

NDN can operate over existing Internet infrastructure through gateways and supports features such as in-network caching, multicast-like content distribution, and mobility resilience. Several open-source implementations and simulation tools exist, including libraries and simulators used by researchers to experiment with NDN concepts.