Both of these terms are used regularly in the IT world (NAS is used very frequently throughout the tech industry) but many people still have no idea what they mean. Both of these acronyms are associated with providing storage solutions across a network. NAS stands for Network Attached Storage and is a single device that operates on data files. SAN stands for Storage Area Networks, and is a local network composed of multiple devices operation on blocks.
A NAS isn’t just found in businesses and organizations anymore as many household solutions are now available. Network storage devices were not very useful for the household user a few years back, but with the trend in digital media shifting many companies are offering NAS solutions to target “personal clouds” and other storage solutions for the home. Especially with the rise of mobile devices such as tablets and smartphones which do not have much local storage, network storage has become a very appealing option for many. Movies, pictures, and documents can be streamed by all of your devices on the network without taking up hard drive space on each one.
SAN on the other hand is almost exclusively limited to the business world (or very tech savvy enthusiasts) as this storage method can only share files between server class devices with SCSI fiber channels. NAS handles both storage and file systems, whereas SAN only handles the storage aspect, and leaves the file system to be managed by the server or on the “clients side”. It can be thought of as the NAS appearing to the operating system as a “file server” where SAN would appear as a disk. With a NAS the OS can go in and map network attached drives as shares on the server, but SAN has to be accessed through disk management utilities. It sounds as if NAS is far superior than SAN but in application the two are used far differently. SANs can be used through fiber channels up to 10km, and are much quicker with data handling. NAS is slower and relies on traditional cabling such as ethernet, but can also work through wireless channels.
In practice the NAS is designed for every computer on the network to be able to access its data- with the right permissions set, where as a SAN is used for servers to share data, isolated from the general traffic in the network. This is where it becomes apparent why SANs are only for organizations, as small businesses that don’t generate a lot of traffic on their networks would not need a SAN. Also, in reverberation the speeds in a SAN are far quicker than NAS spinning at 15000 rpm compared to 7400rpm, respectively.