Wireless telephone service subscription data user access method

Method for providing a user with access to subscription data in a wireless telephone service network including a distribution network having fixed stations and wireless digital telephones linked by radio to said fixed stations, a digital public switched telephone network to which each fixed station is connected, service control points connected to said public switched telephone network and each containing a wireless telephone service subscription database and a call processing logic device for generating a call ticket at the end of each telephone call, a service management system for processing each call ticket to generate a billing ticket and containing a reference database storing the characteristics of each subscription and all said billing tickets, said method comprising the steps:

• storing and keeping up to date in real time in a reference database file of the service management system, billing tickets classified by subscription;
• designating a subscription of interest;
• setting up a link between a user terminal to a server of said service management system;
• using a smart card connected to said terminal to determine a first signature using a random number and a secret key specific to said user;
• transmitting said first signature to said service management system;
• reading the data of said subscription of interest in said reference database to recover said secret key associated with said subscription;
• computing a second signature using said secret key read from said subscription data and said random number;
• comparing said first and second signatures;
• authenticating the identity of said user if and only if said first and second signatures are identical;
• ascertaining the user's access rights;
• reading billing tickets corresponding to said subscription of interest in said database file into the user terminal, according to the user's access rights thus ascertained;
• and
• processing the information from the billing tickets thus read.