Abstract: Disclosed is an apparatus for establishing an IP level connectivity between internet access terminals using a service gateway including a first ISP network connected at one end thereof to a first terminal having an inherent IP address and at the other end thereof to an internet network, the first ISP network including a service gateway for executing authentication of a subscriber of the first terminal in accordance with a service request of the first terminal and communication with other service gateway; a second ISP network connected at one end thereof to the internet network and at the other end thereof to an ATM network to which a second terminal having no inherent IP address is connected, the second ISP network serving to establish an IP level connectivity between the first and second terminals if the first terminal requests connection to the internet network for service use along with the second terminal.

Abstract: The present invention relates to a communication network disturbance management method using a top-down method which detects, analyzes and solves a problem by analyzing a quality state in regard to whole communication network lines. The disturbance management is performed in the whole communication network, thereby managing the communication network problems which are not notified by the users. In addition, the communication network problems can be managed before the user's dissatisfaction notification or disturbance generation. Moreover, the disturbance management access method is based on service quality values, and thus it is possible to manage the communication network problem causing reduction of the service quality provided to the users. As a result, the present invention can provide high quality communication service to the users using the communication network.

Abstract: The present invention relates to a method of extracting a call set-up failure probability and a premature disconnect probability, which are factors for accessing the quality control of a data network. In accordance with the present invention the method comprises the steps of configuring a database for causes of premature disconnect and a configuration database which stores quality values which includes originating and destination numbers. Reading the corresponding billing record and verifying whether the record is normal, and if so, determining whether the origination/destination number of the billing record is the same as that stored in the configuration database. Updating a statistics database for each configuration database, each origination/destination call, each time and date when the numbers match, and then calculating the call set-up failure probability and premature disconnect probability for each configuration database, call and each time and date of the statistics database.