Coputer or NAS

Hello,
In the last few month I started to use in my system Logitech Squeeze box Touch with my work laptop computer and external hard drive. Recently I purchase a DAC(PS Audio Nuwave) and I want to have a dedicated computer or NAS for the system. My goal is to use computer/NAS, SBT, DAC, and Use the Ipad as a remote. Since I’m not a computer guy, I have few basic questions:
1.I’m not familiar with NAS, and I wanted to ask if it’s mandatory to use computer with NAS, or can I use only NAS.
2. My DAC support files up to 24/192 kHz. Does the computer/NAS need to be connected to the SBT or can the computer/NAS be in a different room and transfer 24/192 files using WiFi?
Thanks.