Technical Challenges In Integrating SAN and NAS Technologies

摘要

Digital program content and associated metadata are increasingly represented as data structures contained in data files. Postproduction and program distribution are increasingly being accomplished using Information Technologies (IT) based technical infrastructures that allow content to be efficiently shared, managed and protected. Network Attached Storage (NAS) and Storage Area Networks (SAN) are the "video recorders" in these IT based technical infrastructures. SANs and NAS can transport and store any video format since all video formats appear as standard data blocks and files to the IT infrastructure. Video applications are isolated from physical aspects of SAN and NAS storage by the Operating System that perceives the SAN as a SCSI resource and the NAS as a file server. This paper summarizes some of the technical issues that a system designer will need to be aware of when implementing SAN and NAS based technical infrastructures for television production and distribution applications. One key issue discussed is the latency characteristics of the SAN. This paper begins with a short discussion of SAN and NAS user requirements, applications, terms and technologies and concludes with a report on SAN latency and bandwidth performance evaluations and a brief survey of new SAN and NAS technologies currently being developed.