Hi Sidharth,
Backend System is nothing but your ECC/CRM/SRM systems. In your case its your ECC; your front end server is nothing but netweaver gateway. There are different ways to configure your servers for Fiori, please read the following document SAP Gateway deployment options in a nutshell
You need to check your NW Stack also if its <730 or >730? you need to setup accordingly.
nagesh.cr at gmail.com
Regards,
Nagesh