A management method that allows a communication device to benefit from a network connectivity provided by a third party via the operator network. The method includes: receiving, from the communication device, a request for attachment to the operator network and an identifier of the third party; obtaining, using the identifier of the third party, contact information of a software control gateway instantiated for controlling access to a network slice allocated by the operator to the third party, this contact information including a reachability address of the software control gateway or an identifier of the network slice allocated to the third party and access to which is controlled by the software control gateway; and sending a message to the device containing the contact information and inviting the communication device to attach to the software control gateway using this contact information.