Digital Living Network Alliance (DLNA® *) is a standardized communication protocol that allow compatible devices to share media files (music, photos, videos) through a network made of DLNA® * Certified® devices. detailed information on www.dlna.org.
A Local area network (LAN) is a computer network that interconnects computers in a limited area such as a home, school, computer laboratory, or office building using network media.[source: wikipedia]
A Network access server (NAS) is a computer network device used for storing media and files and having them available remotely from any other devices of the network.