I am very keen on learning how NAS like pogo and mybookworld works? May

My questions are:

1) What are the minimal linux components to create a server like that (small in size, yet working)?

2) How do they create their devices which works behind the NAT and get authenticated through their central server?

3) How can something like DBRD be used to synchronize two NAS?

I tried to figure out this online but I could not. Any hints will be appreciated. Thanks!!

Your questions a) sound like homework b) are not specific enough. We're here to help, not to do you work for you.

@Alucard: You sound too snobbish, sorry to say.

I don't think I asked anyone to do my work nor it sounds like homework. I was just trying to figure out what myworldbook or pogoplug (as they are based on linux) transmits to the centralized server before I deploy them for my personal stuffs. The question is my endeavor to understand the privacy and security stuffs behind those devices while trying to learn the technology behind them.

I am neither for an argument nor a conflict, but still interested to learn. I think that is not something wrong, is it??