Technique for downloading a network access profile

A technique for downloading a profile for access to a communication network by a security module. This access profile has been prepared by a network operator and is available from a server configured to provide this access profile by downloading to the security module. The security module obtains a first verification datum prepared by the network operator. A secure downloading session is established thereafter. During establishment, session keys are jointly generated between the server and the security module and the server is authenticated by the security module using a public downloading key. The security module verifies authenticity of the public downloading key by using the first verification datum enabling verification that the server uses a secret downloading key corresponding to that provided by the network operator during preparation of the first verification datum. When the public downloading key is not authentic, the security module interrupts downloading of the access profile.