VPNs used within organizations allow you to communicate private information securely over a non-private network. You may need to configure VPN, for example, to access your work email. Ask the network’s administrator for the settings necessary to configure VPN for your network. After one or more VPN settings are defined you can:
Turn VPN on or off: Go to Settings > VPN.
Switch between VPNs: Go to Settings > General > VPN, then choose a configuration.
See also iPhone in Business.