File Sharing Via Internet

Hi

I bought my ReadyNas Duo v2 (ARM) a few months agao and have satisfactorily integrated it into my home network and can stream files ok.

I want to allow my family to share my ReadyNas's contents and download & upload stuff from & to it from time to time, via the internet.

I am very confused about this - I thought Plex would do it via "myplex" but I have just learned that it will only stream the files.

What I want is for my family, dotted across the UK to be able to log into my server, perhaps with a password, and see thumbnail images of the files and then be able to download what they would like, namely family photos and videos etc. I would like them to be able to upload files to the server too.

Could you point me towards suitable software which I can use on the readynas in this respect and which is easy to install, configure and use. I would like my family to be able to use it easily too.

Thank you in anticipation

roz