What is the difference between a NAS and a SAN, so that is the topic of this video so we'll first talk about what a NAS is. Now NAS or N-A-S stands for network attached storage If you wanted to store data in a centralized location, where it can be accessed from all of your devices on your network You can do this by using a network attached storage device. A NAS is a storage device that is used for storing data, and it doesn't do anything else besides storing data.
Now typically a NAS is a box that will have multiple hard drives in a RAID configuration for redundancy and it'll also have a network interface card that will directly attach to a switch or router So that the data can be accessed over a network, then once it's on the network It can be accessed from other devices Such as desktops, laptops, and servers and it can be accessed as a shared drive Now NASs are typically used in homes and they are also used in small to medium-sized businesses But one of the main disadvantages with a NAS is that it has a single point of failure So as an example Let's say if a component fails such as if the power supply fails on the NAS Then all of the other devices will not be able to access its data Now a SAN or storage area network is a special high-speed network that stores and provides access to large amounts of data So basically it's a dedicated network that's used for data storage and this network consists of multiple disk arrays, switches, and servers. And because it has more than one of these devices, a SAN is fault tolerant And the data is also shared among several disk arrays So if a switch or disk array or if a server goes down the data can still be accessed And when a server accesses the data on a SAN, it accesses the data as if it was a local hard drive Because that's how operating systems recognize a SAN it's recognized as a local attached hard drive rather than a shared network drive like in a NAS. And SANs are also highly scalable because adding more storage space can easily be done without an interruption on the network So as stated before a SAN is a high-speed network And that's because in a SAN all the devices are interconnected Meaning that all of the devices are connected to each other and they are interconnected using fiber channel which is a standard for SANs.
Fiber channel is fiber optics and it has speeds between 2 gigabits per second all the way up to 128 gigabytes per second. So fiber channel is extremely fast and it's also very expensive and most SANs today use fiber channel But also as an alternative to fiber channel some SANs use iSCSI instead Which is a cheaper alternative to fiber channel, but it's also not as fast as fiber channel Now one of the main reasons for using a SAN is because SANs are not affected by network traffic Such as bottlenecks that can happen in a local area network And this is because SANs aren't really a part of a local area network SANs are partitioned off. It's basically a network all by itself and other reasons for SANs as I mentioned before SANs are highly scalable and they are also very redundant.
