Patent ID: 11936675
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 19:
20. A non-transitory computer readable medium storing computer executable instructions which, when executed by a computer, cause the computer to execute:
receiving a device ID for identifying a device in a private network and an observation event that has occurred in the device as an input;
acquiring, from a device information memory, attribute information of the device corresponding to the device ID;
estimating a risk that the device in the private network is subject to an attack, based on the acquired attribute information and the observation event, by:
first calculating a first probability that the device is subject to unauthorized access from a public network;
second calculating a second probability, based on the first probability, that the device is subject to unauthorized access to the private network;
third calculating a third probability, based on the first probability, that the device is subject to unauthorized input to network provider of the private network; and
estimating the risk based on the second probability and the third probability; and

outputting a state transition diagram which illustrates a step-by-step process of estimating the risk, the state transition diagram including formulas for the first calculating, the second calculating, the third calculating and the estimating.