The choice

Depending on your needs, there are a few different roads you can take:

• maybe you just want to backup one computer, or you have just one TV or media player with a USB connection; in this case you may not need a central server and an external USB disk may suffice (USB 3.0 preferred); you may also have backup software included
• if your decide you need some form of central storage but your need are pretty basic and you prefer to “keep it simple”, you may go for a ready-made device, with disk (or disks) included; on the market you can find devices with 1 or 2 (with RAID 0 or 1) disks and different capacities at reasonable prices, like those from Western Digital or LaCie; those will usually offer at least DLNA and iTunes servers, easy remote administration and some sort of backup software, and lately phone applications and “personal cloud” features; generally, this devices include lower performance chipsets and you will probably get even lower speed than with USB 2.0 devices
• going up the scale, you can go for a BYOD (bring your own disks) device; this will come with 1, 2, 4, 5 or even more disk bays and various level of performance; higher end devices can have speed around 100 MB/sec, close to the theoretic limit of gigabyte networks (125 MB/sec); some devices can have dual LAN interfaces, but this are probably overkill for home; devices in this category have a very long list of features – over the usual things like media servers and remote administration you will get user accounts with space quota, ftp, download managers, remote file managers, and maybe even web, database and mail servers or IP camera connections; you can get multiple RAID levels, automatic RAID rebuild, RAID grow, timed standby, mail alerts and more; producers like Synology, Qnap or Thecus have a large offer for different level of performance and space requirements, but usually with more or less the same software features (they use the same operating system on all devices); of course this are not the only producers around – Netgear, Buffalo Technology, Dlink etc; keep in mind that the higher end (high performance) devices can be expensive
• and of course you can build your own server; this way you can choose exactly what you want the server to do, and you may get a high performance server for a much lower price than the equivalent BYOD device; the downside (or upside, depending on your view) is that you have to do it yourself and learn a few things in the process ; the price will depend on the performance level you want (especially if you want your server to do more complex things or a lot of processing at the same time), the cooling, the noise or the size (you will most likely not find a casa as small as that of a pre-built NAS device, and if you want a small case with support for more disks – you will have to pay more); depending on needs, you may also reuse component you already have

If you decide to build your own server, you must also chose the software for it:

• Windows – the most common OS, with graphical interface; but it will also need more resources to run and it will cost (less for Windows 7 but with limitations, more for Windows Server, and there is also the Home Server version)
• specialized home server Linux or BSD distribution, like FreeNAS, ClearOS or Zentyal, with built-in administrative web interfaces; you may have to check your hardware compatibility or if the software you need exists on the chosen distribution
• generic Linux distribution – usually this should have broad hardware compatibility and support lots of software – Ubuntu, Debian, Fedora, OpenSuse; you may also have a special server version, from which to start building your system (like Ubuntu Server); web administrative interfaces like Webmin can be used