How to set up time machine with RT-N56U and Synology ds212j

I have the ASUS RT-N56U router and the Synology ds212j NAS, however I wish to set up backup for my Macbook Pro using the Time machine, and as I am new to this, I would like to request your help.

I have started the Time machine in order to set it up - but all that happens is that it keeps on ticking forever and ever looking for some Airport device which I don't have. I haven't been able to set it up at all. Will it still be possible to perform backups using other routers and NAS than Apple's own? Surely it must!

Thanks for all your input!

The best

ptk