No longer do you need to run around the house turning PCs on and off just so that you can access the shared files on them. No more file access interruptions due to a family member accidentally turning off the shared PC. You will also no longer have to put up with degraded performance on your PC when shared files are being accessed by others.
In addition, data also becomes more manageable and cost efficient when centralised. Without the need to keep multiple copies of the files in individual PCs, you get to save on hard disk space and eliminate file synchronisation and versioning issues. To improve reliability and availability of the data, you only need to invest in RAID for your central file server instead of all the individual PCs.
And lastly, a centralised file store can also serve as a cost effective and efficient means of backup for your other PCs as compared to using removable USB drives or DVD media on each of your PC.
A NAS (which stands for Network Attached Storage) is basically a stripped down computer that primarily serves files on your network. You can choose to build your own using your old hardware (since its essentially a PC), or buy one off the market. Here's my take on why its better to buy than build (or reuse your old hardware) one.
- Space saving - Dedicated NAS boxes are no larger than the hard disks they packed. Therefore, they consume much smaller real estate on your desktop, bookshelf or any other location you choose to place them as compared to normal workstation cases (even the micro ITX ones).
- Low power consumption (and consequently low heat and noise) - Dedicated NAS boxes usually pack components that have just enough juice to run the file services hence they also have much lower power requirements as compared to normal general purpose workstations. One common misconception here is that by using older generation of workstation components (e.g. your five year old Pentium IV CPU), you can achieve the same results. On the contrary, they generally consumes more power (and generate more heat) than compared to modern hardware with similar performance due to technological improvements in design (e.g. lesser components used) as well as manufacturing process (e.g. miniaturization).
- Cheap - You will be surprised to know that a decent two bay NAS can start from just S$200 (without hard disks) and at the lowest end, you can even get a single bay NAS for under S$100. Even the cheapest barebone workstation (casing, power supply, mobo, CPU, RAM) around will probably cost more. Another common misconception here is that it (buying a new dedicated NAS box) still cannot beat your old retired workstation which is "free" (technically it is not since you did pay for it when you first bought it for a different purpose). But do remember that in the broader picture, other than the initial purchase price that you pay, you have to take into account your older hardware will probably consume more power, more prone to failure and not covered under warranty thus resulting in higher running costs.