VPN is a Virtual Private Network. It extends a private network and the resource contained in the network across public networks like the Internet. It enables a host computer to send and receive data across shared or public networks. It establishes a virtual point-to-point connection through dedicated connections and encryption or the combination of the two. Virtual Private Network can be classified as:
1. Protocols used to tunnel the traffic.
2. Levels of security provided.
3. Tunnel's termination point.
4. Site-to-site or remote access connectivity.
5. OSI Layer.
VPN works on Architecture, Tunneling, Authentication, Encryption, Addressing & Routing, Firewalls, NAT and related information. Mobile VPN is a service provided by PSMail. It is a private networking system that makes the public internet to tunnel traffic secretly and securely from mobile phones or PC's to a computer network. This method allows you to access safely your PSMail and the other Internet resources from a limited or unsecure network connection.
Currently some of the mobile phones and tablets are supported by VPN are iPhones of version 4 and iPads of version 4, Samsung, HTC, Lenovo are the Androids supported by the VPN.