CENTERALIZED VPN MANAGEMENT SYSTEM

we need a centralized VPN management system where we can Manage all servers and user on One platform. This system should have API to control it externally. In thìs system we can Add and Remove servers and on one click we can install openvpn server. under central system we can add user manually or through API user will be created. we can set bandwidth limit, view bandwidth usage, block website/torrents and logs etc. we can check connected devices stauts like device or pc name should be visible. we can set things like subnet behind client Routes. when we will creat user Keys and OVPN fill will be created with respective user. We will have openvpn,PPTP, L2TP, SSTP protocol we need strong encryption both udp and tcp we can change port anytime for single server or multiple server from central system. We need API for backend server and front end for website and Apps. additional requirement can be added later upon discussion.