Encrypt traffic with VpnService

Question

I've searched for a solution for 2 days. The problem is: i need to create the app for encrypting (with some custom algorithm) all internet traffic from a device. I've found that I can use vpn and android provides me a class VpnService . I don't understand how to encrypt the tcp packets with VpnService class.

Could anyone help me please?

Answer 1

By using VpnService, you can get all the IP packet routed to your interface. What you get here, is IP packet, which takes TCP/UDP packet as payload. The the IP packet should be tunneled to remote server. Encrypt the traffic with remote server is what you need.