In this age of high-resolution photos and near-constant video capture, the storage space in your PCs and mobile devices fills up faster than ever. While you can certainly use an external hard drive for offloading and backing up files from your PC (and by extension, your phone), if you disconnect the hard drive and leave it in your office, you won't be able to get to those files from home, and neither will anyone else. There are ways to allow other users to access the files on your hard drive, but they may be challenging to implement, or carry security risks. Instead, consider a good network-attached storage (NAS) device. As its name implies, a NAS is high-capacity storage that connects to your home or office network so that you and other users you designate can access your files from mobile devices and PCs without plugging in to the drive. Here's what you need to know to choose the right NAS.
What Can You Do With a NAS?
Once you decide that you need to store files on a network drive, you then need to figure out what you want to do with them in order to determine what kind of NAS you need. For example, sharing access to Office files like spreadsheets and Word documents with your coworkers is a relatively simple job for a NAS. If you're using the NAS to back up your laptops overnight, that's pretty straightforward as well. But if you're serving HD videos over your home network to two tablets, a laptop, and your smart TV simultaneously, you'll want a NAS with higher specifications for memory, processor, and network capabilities. You'll also need a more powerful NAS if you want to store media libraries, like a collection of 100,000 stock photos, for your graphics art studio. Our NAS device reviews point out their capabilities and suitability to various tasks.
Storage Capacity
Another factor to consider is how much storage capacity you need. The simplest NAS device has space for one internal hard drive, but more complex units can have two to eight or even more drives. For backing up a couple of PCs or your family's phones, 1TB to 2TB should be sufficient. If you're a media enthusiast with a large digital video collection, you want at least 6TB to 8TB of space. For a small office or workgroup, consider a NAS with 10TB to 20TB. You can even reach into the hundreds of terabytes and pay out significant cash for a NAS setup for a large office that stores a lot of files locally. Larger offices may also want use rack-mounted Linux or Windows file servers instead, as those come with integrated functions like email and Web servers.
The Cost Factor
Basic NAS units with a single 2TB hard drive start at around $150, but the more complex the NAS, the higher the price can go. For example, a basic home NAS with two preinstalled hard drives, like the Western Digital My Cloud Mirror, starts at about $399 with a 4TB capacity, while a two-bay, business-oriented model like the 2TB Buffalo TeraStation 5200DN goes for $450. A diskless NAS may seem like a bargain at around $250, but you'll have to budget another $100 to $200 for hard drives to install yourself. A business-class NAS, like the $1,529 Western Digital My Cloud DL4100, has four preconfigured 6TB hard drives for a total of 24TB of storage space.
Disks or No Disks?
You can purchase a NAS with its hard drive or drives preinstalled, or you can buy a so-called diskless NAS, which has empty bays that you populate with drives yourself. A NAS with included drives is, of course, easier to set up, but it can be pricier (as we pointed out earlier), especially if you only need 2TB of space now, and remember that your storage needs may grow with your business down the road. In our NAS reviews, we state how much drive space is available preconfigured, and the cost or capacity of potential upgrades if the NAS is sold diskless. A NAS with multiple drives will usually use some form of RAID to keep your data safe. For more on what that means, read RAID Levels Explained.
Connectivity
NAS boxes serve files to multiple PCs and mobile devices over a wired LAN or Wi-Fi network. Most connect to your router via Gigabit Ethernet. A few NAS appliances have built-in Wi-Fi, but they are rare. Most wireless transfers will go through your home or office router rather than directly to your laptops and phones over the air.
Components
Like a PC, a NAS device has a CPU and memory, as well as an operating system (usually a proprietary Unix or Linux OS). A model with 512MB of system memory and a dual-core processor is certainly sufficient for a family with a half-dozen devices total, but you may want to look for a NAS with at least 2GB to 8GB of memory and a quad-core CPU for your office workgroup. Most NAS units will have energy-saving processors based on ARM or Intel Atom CPUs, but if you need to support multiple devices for more than just daily backups, then a NAS with a more powerful chip and more memory will help out in the long run. This is especially true if you're serving 1080p HD and 4K video to your laptops and mobile devices.
Software and Setup
All NAS devices come with an operating system, but it's not like the operating system on your PC. For one thing, PC operating systems like Windows 10 let you run any compatible software, from Web browsers to accounting programs. NAS operating systems whittle the functionality down to file storage, file transfer, user access, and keeping the NAS running efficiently.
A NAS device intended for home or small office use is designed to be easy for you to secure and administer. Every NAS we've reviewed uses standard logins with username and password combinations, and you can set up group permissions on your folders, so, for example, your kids can access your stored movies, but not your financial files. Most devices will ask you to run an installer from a CD or DVD, or alternately set up the NAS from a website. The latter can also help you set up remote access from the Internet. Just follow the prompts, and you'll have a multi-terabyte storage unit ready to go in a half-hour or so.
Remote Access and Personal Cloud
Your login credentials can also be used to remotely access the NAS over the Internet, via an online personal cloud account. The personal cloud app on your mobile devices or a website run by the NAS manufacturer (like mycloud.com) automatically handles the connections between your PC or phone and the NAS at home, so you don't have to configure your router for VPN access in order to get to your files remotely. The files are still stored on your NAS at home, rather than on an online server the way they are when you use an online cloud storage service. The benefit of this setup is that your files will be stored on a device you control, rather than an online service that can go down because too many businesses are accessing it at the same time, or because of other technical difficulties, like a cloud server complex going down in Iowa. And you won't have to pay a monthly fee when using your personal cloud on a NAS—it's included for free with most recent NAS units.
Media Playback/Services
In addition to serving media to your devices through an app, home-oriented NAS boxes support local media services like Apple iTunes and DLNA, so you can play your music, view your photos, and watch your videos on compatible devices. That means, for instance, that you can just turn on your smart TV, go to the relevant menu, and view the pictures you backed up to your NAS while you were on your business trip.
Many home and prosumer NAS units can also run third-party apps like Transmission (a BitTorrent client) and Plex (a media server), so you can set your NAS to download, transcode, and serve movies automatically to all your devices once they are available online.
File Security
Many of the NAS devices we have tested support file encryption, and offer a variety of security controls to protect the NAS from intruders. This can range from locked enclosures or security-lock slots to firewall-like access protection.
Below are the top 10 NAS devices we've tested, ranging from simple home-oriented models to multiple-drive arrays that can serve dozens of users in an office environment. Whether you want to serve media files to the rest of the house, keep office documents in a single, accessible repository, or simply back up your digital life from your PCs, tablets, and mobile phones there's a drive here for you.
For more storage options, take a look at our lists of the best external hard drives and SSDs, as well as our top-rated cloud storage services.