Thank you sir, I am really thankful to you for your suggestion. Now I am starting work with "https://community.openvpn.net/openvpn" as you suggest me. sir I am working on the client end . I want to connect my VOIP application using VPN. means I want to implement VPN in my Mobile dailer VOIP application. I need the VPN code in C language because I think this is easy to implement in every Mobile Dailer(symbain, windows, Iphone, android). Will you please help me sir. If you dont mind ..can you please give me your personel Email ID or mail me on"nishadamit09@xxxxxxxxx". Thank you sir