A method is proposed for configuring a terminal by using a server in an IMS communication network. The method includes: receiving an SIP registration message from a terminal, the registration message having at least one parameter relating to the access network, obtaining a configuration from the parameter relating to the access network included in the registration message received, and transmitting to the terminal a response to the registration message, the message having the configuration obtained from the parameter relating to the access network. Correlatively, a method is proposed for obtaining a configuration on a terminal.