This invention describes “plug and play” methodology for configuring a terminal, enabled for handling data-protocol services (e.g. GRPS), for the data-protocol services specific to a service provider so as to be able to connect said terminal to an IP backbone network via a network, which provides said data-protocol services and which is provided by said service provider. The invention further consists of using a well-known access point node (APN) name, and a well-known uniform resource locator (URL) string to access a service provider specific help-portal server of the network to request information for configuring the terminal. A core part of the invention is the fact that the security of the download is ensured by means of a chain of trust that originates with a trusted home location register or the well-known APN name, and is built using a trusted APN, the well-known URL string and a trusted domain name service.