DECnet is a proprietary suite of network protocols created by Digital Equipment Corporation, originally released in 1975 in order to connect two PDP-11 minicomputers. It evolved into one of the first peer-to-peer network architectures, thus making DEC into a networking powerhouse in the 1980s. From a technical standpoint DECnet was built right into the DEC flagship operating system (VAX/VMS), being the foundation for the first cluster architecture ever designed, the VAXcluster. Initially built with four layers it later (1992) evolved into a seven layer OSI compliant networking protocol, around the time when open systems (POSIX compliant

DECnet refers to a specific set of hardware and software networking products which implement the DIGITAL Network Architecture (DNA). The DIGITAL Network Architecture is essentially a set of documents which defines the network architecture in general, states the specifications for each layer of the architecture, and describes the protocols which operate within each layer. Strictly speaking, non-routed DIGITAL protocols such as LAT, SCS, AMDS, LAST/LAD are not DECnet and are not part of the DIGITAL Network Architecture.