NAS Buying Guide

A network-attached storage (NAS) device is like an external hard drive, but one that has its own network address and connection. That way, additional storage is potentially available to every device on your network. Moreover, it lets you back up content from all your networked computers and access that content from anywhere on your network or over the Internet.

An NAS is a good way to add storage capacity for large data files, such as images and videos, and make them easier to share across your home or office network. It can also be a more reliable way to store information than on a computer's hard drive, thanks to "redundant array of independent disks," or RAID technology, which we'll get to in a moment.

In this buying guide, we'll show you how to pick the right NAS for your needs. Storage can be a very technical subject, so we've come up with three core types of users to narrow down the options and give you a quick recommendation. Then you can read on to learn more about key features and critical decisions.

Cut to the Chase

Let's identify your NAS needs and pinpoint a model. Which kind of user are you?


Householder. You need backup, recovery, and file sharing, but you can't spend a fortune. You use the Internet mostly for Web surfing and email tasks. You don't have a large collection of media files.

Recommended features:

  • Scheduled automatic backup
  • Printer sharing
  • Web file server

Recommended model: D-Link ShareCenter 2-Bay Network Storage (DNS-320-1TB or DNS-320 if you prefer to add your own drives)

Media mogul. Your storage needs are more demanding than those of the Householder. You have a large collection of digital media files and you want to enjoy them via computers, network-connected televisions, iPads, and media streamers such as the Boxee Box by D-Link. Thus you'll want a faster processor to handle an increased network load as well as support for streaming media. You also want an NAS that helps you organize photos and shows galleries of thumbnails when you browse its contents.

Recommended features:

  • Automatic backup
  • Printer sharing
  • Streaming media

Recommended model: D-Link ShareCenter 2-Bay Network Storage (DNS-325-1TB or DNS-325 if you prefer to add your own drives)

Office manager. You need continuous access to your data, so it needs to be backed up and always available. If a storage disk fails, you want to be able to swap it out and restore your NAS quickly and painlessly. If you're in a large office, you'll want the higher storage capacity provided by four drive bays and extra disk redundancy.

Recommended features:

  • Scheduled automatic backup
  • Gigabit Ethernet
  • RAID 5 Data Protection
  • Printer sharing

Recommended model: D-Link ShareCenter 4-Bay Network Storage (DNS-343-4TB or DNS-343 if you prefer to add your own drives)

NAS Features

Not all NAS devices are created equal. Different models offer various capabilities that can make the device suited to particular situations or simply make life in the digital age a little easier. Here's a rundown of the most important features to consider.

Automatic backup. For trouble-free data security, look for an NAS device that includes automatic backup software that supports scheduling. The device must have plenty of extra storage room. Consider the D-Link ShareCenter DNS-320, DNS-325, or DNS-343.

Gigabit Ethernet. For the fastest network transfer speeds, look for an NAS unit that offers Gigabit Ethernet connectivity. A wired connection, Gigabit Ethernet ensures that audio and video files will stream without dropouts or pauses, and larger files will take less time to upload and download. All D-Link ShareCenter NAS devices include this feature.

Hot-swappable disk drives. For business-critical data, consider an NAS with hot-swappable drives. This means you don't have to turn off the power to your NAS to replace a failed drive, so the NAS can continue to operate and share files. Easy access to the drive bay makes replacing drives a quick operation. Beware of sealed NAS devices that force you to open the case to remove a drive, voiding the warranty. All D-Link ShareCenter units can be opened for drive replacement. The D-Link DNS-320 and D-Link DNS-325 feature hot-swappable drives.

Printer sharing. If you want to share a printer on your home or office network, an NAS with a USB printer-sharing port provides a good way to do it. Simply connect the printer and it will be available to every computer on the network. (If your printer is a multifunctional model with copier, scanner, and fax, you won't be able to access those other functions from the NAS.) The D-Link DNS-320, D-Link DNS-325, and D-Link DNS-343 all include this feature.

Streaming media. If you want to stream -- rather than just store and share -- audio and video from your file server, your NAS should support one or more of the following streaming technologies:

  • DLNA (Digital Living Network Alliance)
  • Apple iTunes Server
  • Logitech SqueezeCenter
  • SMB (Samba) Support
  • UPnP AV Server

Your media player (such as Windows Media Player, iTunes, or the Boxee Box by D-Link) will determine what media server function you'll need. Here's a chart showing which standards are supported by which D-Link NAS devices.

Web-based management. Some NAS devices include simple tools for establishing user accounts with storage quotas and access rights, among other tasks. They're particularly useful if you want to control your data while it's being shared with others on your network. You don't need to install any special software to manage your NAS. Simply bring up its Web portal page in your browser and navigate the graphical menus to make your choices. All D-Link ShareCenter NAS devices include this feature.

Web file server. While all NAS devices can share files on a local network, you might also want to share them across the Internet. This way, you have remote access to your data from any Internet-connected computer, no matter where you are. The D-Link DNS-320 and D-Link DNS-325 come with a built-in Web file server.

Critical Decisions

Now that we've gone over the most important features, here are the decisions to make before you settle on an NAS model.

Storage capacity. How much space do you need? Drives come in a variety of sizes. A 1-terabyte (1TB) drive can store more than 300,000 digital photos, or 16,500 hours of digital music, or 250 DVD-quality movies. Here's a rule of thumb that can help you decide: Tally the amount of storage you presently consume and triple it to account for growth. As you can see from the numbers, video can eat up a lot of storage compared to other data formats, so plan accordingly.

Built-in drives vs. diskless. The most important part of any NAS is its disk storage, and you can purchase an NAS with built-in drives or buy them separately. D-Link offers both types of configuration, and there are tradeoffs either way. Built-in drives come pre-tested, guaranteed, and ready to use. There's nothing to configure. However, if you prefer a particular vendor's brand or would prefer to shop around, then diskless is the way to go. It's generally easier to replace a failed drive if you've purchased your own disks, as some NAS devices that include drives don't let you open the case and replace them (though this is not the case with D-Link's offerings). The D-Link ShareCenter page offers great information on how to pick compatible third-party disk drives.

Security. Consider how you'd like to share files among family or office workers. Do you need common storage areas that everyone can access? How about areas that are protected by passwords to prevent unauthorized access? All D-Link's NAS units can create both types of storage. You just need to plan accordingly.

Data value. In planning your storage needs, it's important to assess the value of the files you intend to store: Are they irreplaceable family photos? Are they critical to the daily operation of your business? Are they backups of your music CDs and videos you already own, or downloaded music that, in case of loss, you would have to repurchase? The more precious your data, the more critical it is that you have a backup system in place.

Data protection. Once you have a sense of how valuable your data is, then you'll know to what lengths you should go to protect it -- whether something low-key is just fine, or whether you need a really bomb-proof solution. Let's run down the options.

In the most basic setup, an NAS device can store data in a single volume on a single physical disk drive. D-Link refers to this arrangement as standard mode.

This setup might be fine for the Householder, but it won't work for the Office Manager -- it doesn't provide enough data security. After all, disk drives fail. To cover this possibility, many NAS devices house more than one drive, and multiple drives can be set up to store identical copies of your data. The good news is that this kind of protection used to cost thousands of dollars and required specialized knowledge, but with D-Link NAS products, a robust storage system is affordable and easy to set up.

To cover the possibility of drive failure, you need multiple drives set up in a configuration known as RAID, or redundant array of independent disks. RAID comes in different styles that are identified by number. For iron-clad data protection, the numbers are 1 and 5. It's important to remember that, while a NAS device might support multiple RAID numbers, once you settle on one, you can't easily change to another.

In RAID 1, which is supported by all D-Link NAS units, one drive mirrors another, storing the same data in two places. If one drive fails, there's a copy on the other. You give up half your total storage capacity, but in return you get rock-solid reliability. RAID 5 requires an NAS device with three or more drives, such as the DNS-343. Here, one drive is used for error checking. With four drives installed, you give up only 25 percent of the unit's storage capacity, but you gain a lot of protection.

The ideal setup is RAID protection along with an automated, scheduled backup that regularly duplicates your data.

Capacity and convenience

NAS lets you scale up storage capacity as you need it, for an increasingly larger collection of digital images, video, and other files. At home, a NAS unit can enhance your entertainment system and your small office, and the whole family can take advantage of it.

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