To build a VPN - Virtual Private Network - various conditions have to be fulfilled. The authentication of the partner, a standardised encryption as well as the access control and embeddening in the security structure of the company - together they establish the favoured private network. The build up of communication channels by means of an unitary technology as tunnel to the communication partner via the Internet is a cost-effective possibility (approx. 3:1) compared to the previous solutions via user-to-user connection/standard telephone line (Standleitung) respectively conventional dial-in-methods/dial-up connections (Einwahlverfahren) (RAS-technology). There are different encryption methods to choose from (Preshared, RSA, X.509-certificates). Basically they are combinations of public and private modes and the choice what shall be encrypted. Encrytions are also offered in combination with Securepoint Firewall Systems. Securepoint supports the VPN-standards PPTP and IPSec.