Computer-implemented method for configuring an access protection system (FW) suitable for regulating a data communication connection of a computer-implemented application (APP) between a first computer network (NW1) and a second computer network (NW2), wherein - the computer-implemented application (APP) is provided (S1), - an image of the first computer network (NW1') is provided in a test system (TE) and the computer-implemented application (APP) is executed (S2b) therein, wherein the image is a reconstruction of the first computer network comprising all relevant network components and connections, and wherein the test system is shielded from other communication relationships, with the result that only those communications which are relevant to the computer-implemented application are carried out in the test system, - a data communication connection (DC) between the image of the first computer network (NW1') and the second computer network (NW2) that is required when executing the computer-implemented application is determined (S3) by a sensor , - on the basis of the data communication connection (DC) determined by the sensor, a configuration rule for the access protection system (FW) for allowing the data communication connection (DC) of the computer-implemented application (APP) between the first computer network (NW1) and the second computer network (NW2) is derived (S4), wherein the configuration rule is derived in such a way that only a trusted and/or permitted data communication connection (DC) of the computer-implemented application (APP) is allowed via the access protection system (FW) according to the configuration rule, and - the configuration rule for configuring the access protection system (FW) is output (S5). - the computer-implemented application (APP) is provided (S1), - an image of the first computer network (NW1') is provided in a test system (TE) and the computer-implemented application (APP) is executed (S2b) therein, wherein the image is a reconstruction of the first computer network comprising all relevant network components and connections, and wherein the test system is shielded from other communication relationships, with the result that only those communications which are relevant to the computer-implemented application are carried out in the test system, - a data communication connection (DC) between the image of the first computer network (NW1') and the second computer network (NW2) that is required when executing the computer-implemented application is determined (S3) by a sensor , - on the basis of the data communication connection (DC) determined by the sensor, a configuration rule for the access protection system (FW) for allowing the data communication connection (DC) of the computer-implemented application (APP) between the first computer network (NW1) and the second computer network (NW2) is derived (S4), wherein the configuration rule is derived in such a way that only a trusted and/or permitted data communication connection (DC) of the computer-implemented application (APP) is allowed via the access protection system (FW) according to the configuration rule, and - the configuration rule for configuring the access protection system (FW) is output (S5). <EOS>