Effectively a server, a NAS box gives you much more data storage that can shunt data to your laptops, phone and anywhere else you need it. Here's a quick, no-nonsense introduction.
No matter what you use your home network for, you’ll inevitably be shunting data around. Once you start accessing the same data from multiple devices it becomes much easier to centralise this storage – if anything it is a massive waste of energy to boot your desktop PC if you only want to view photos on your television.
Laptop owners will also usually have much less storage than what is available to a desktop user. Laptop chassis fit at most two hard drives, usually just one, and the amount of space available on a single laptop hard drive is much less than on a desktop drive. Expansion usually involves a costly hard drive replacement, so we see the situation where laptop users rely on external hard drives to bulk out their storage.
For the data that you do have on your PC, centralised storage provides a secondary site to store your data. While Cloud backup and the like is becoming more and more affordable, it is still unfeasible for large video collections for example.
Your requirements are going to be determined by the amount of data you have. The big culprits here are photographs and videos, although backing up large PC hard drives can quickly take its toll as well. The other issue is how much need you have for that data. A student household with 3 PCs constantly downloading and streaming video will have much heavier requirements than an average family home where viewing photos and the occasional video, with automated backups, is the norm.
What are the options?
The first port of call is going to be the standard, everyday external hard drive. Most modern routers will come with a USB port or two on the back, designed to take an external drive. This can be a good use for an old portable drive, otherwise something large capacity like one of Seagate’s 3TB GoFlex Desk drives will give you space into the future.
You will likely want to look beyond this at a dedicated network device though. These come in many shapes and forms, and have become quite simple to operate. At the base level sit what are effectively external hard drives with network interfaces. Seagate’s GoFlex Net falls into this category, in this case it is an Ethernet equipped dock designed to take a couple of the hard drives, but there are other dedicated units out there as well.
The best solution for most people is a NAS (Network Attached Storage). This is effectively a server, designed to offer more storage capacity and more flexiblity than hard drives. A NAS can be purchased with hard drives already installed, but there are also a lot of bare bones units available. A four-bay NAS, for example, can be populated with one or two drives now and then have more added to it down the track. This scalability is incredibly important if you engage in data-heavy pastimes.
If you need more than a NAS offers, or maybe have an old PC lying about that you’d like to repurpose then you can build your own. The most common solution for this is a program called FreeNAS, which is built upon the Open Source BSD operating system. Unlike Linux, which has made great leaps and bounds in hardware compatibility, FreeNAS can be a bit finicky with newer hardware. You don’t need a hugely powerful system for this, you can even run the operating system off a flash drive to allow you to dedicate all hard drive space to storage.
Choosing the right network storage
Much like the internals of a PC, a network is an assortment of different transfer protocols and speeds. Performance will ultimately be determined by the weakest link in the chain. For Internet data this is easy, as common consumer connections like ADSL have much lower bandwidth than the rest of the network.
However when you start shunting data between systems you encounter all sorts of bottlenecks. If you transfer some photos from your PC to an external hard drive connected to your router the speed can be affected by everything from the rotational speed of the hard drive platters all the way through to the way that your switch is designed.
Core to all this is network speed. One of the most confusing and annoying parts of working out network bandwidth is that the networking protocols are expressed in Megabits, while most software reports transfers in Megabytes. So you need to keep in mind that there are 8 megabits in a megabyte, so a network running at 100Mbit will be capable of shunting 12 Megabytes of data a second. A Gigabit network should be able to push out 100 megabytes per second.
This all means that the fastest solution is going to be a NAS, preferably using a RAID array running over a Gigabit Ethernet. The slowest is going to be a USB hard drive connected to a router, which has all sorts of hurdles to overcome.
As we mentioned before, pretty much any network design is going to be good enough for Internet data, so the bits and pieces of the network will largely be defined by the speed you need files to move at. If you are just doing regularly scheduled backups then the USB via router solution should be fine, although initial backups will take hours or even days to complete (it is often a good idea to do the initial transfers by plugging the drive into the PC, and then moving it to the router after this is done).
Setting up a NAS
Deciding on the right kind of NAS is a case of identifying your needs now and in the foreseeable future. Those building video collections will likely have a need to increase storage at a decent rate, and digital photographers who want to shoot RAW will be astonished at how quickly all the drive space gets eaten up. If it is just a spot to backup your PC, or is to store something like your iTunes music library, you’ll likely need more space at a much slower rate.
Thanks to the emergence of 3TB hard drives, two-bay NAS boxes are pretty tempting. Seagate’s two-bay Black Armor 220 comes in a 6TB version, packing two 7200rpm Barracuda XT drives, for example. This is an astonishing amount of space, and likely sufficient for all but the heaviest of users, but capacity isn’t the only issue.
While using a NAS for backup already ticks the all important secondary location box, you can further improve your data security by trading speed for redundancy. Most NAS devices will let you configure the RAID array inside (something best done before putting your data on it). This allows you to choose from several options, the most common of which are RAID 0 and RAID 1.
RAID 0 uses a technique called striping to increase data transfer speed. Data gets written alternately to each disk, which allows for much greater read and write speeds than a single drive delivers.
RAID 1 on the other hand uses a technique called Mirroring, where the entirety of the data is written to both disks. This halves the available storage capacity, but is the best way to ensure data redundancy with only two disks.
There are other more complex RAID setups that mix these two types, but a lot of consumer grade NAS boxes just don’t have the computing power to make them viable. That means that your choice will likely come down to retaining all the capacity of your drives, or adding an extra level of data security by choosing redundancy.
The second part of choosing the right NAS box is identifying the extra features you need. Next we’ll dive into the file protocols and media streaming setups needed to get the most out of your network, and ensure that everything interacts smoothly.