Abstract: A system and a method of transmitting data via data networks. A bidirectional data connection is created even behind firewalls, including from a client not visible to a server in the Internet. In the method and system, a first connection request for establishing a first transmission channel is sent to a server of an automation system from a first data processing device of a client via a data connection. This request is answered by the server via a second transmission channel. The data connection is kept permanently open, thereby allowing mutually time-independent bidirectional sending and receiving of data between the client and the server, via at least one data network. A COM automatic marshaller which incorporates itself into the communications chain between the client and the server is provided.

Abstract: A system and a method of transmitting data via data networks. A bi-directional data connection is created even behind firewalls, including from a client not visible to a server in the Internet. In the method and system, a first connection request for establishing a first transmission channel is sent to a server of an automation system from a first data processing device of a client via a data connection. This request is answered by the server via a second transmission channel. The data connection is kept permanently open, thereby allowing mutually time-independent bi-directional sending and receiving of data between the client and the server, via at least one data network. A COM automatic marshaller which incorporates itself into the communications chain between the client and the server is provided.

Abstract: OPC data is transmitted via data networks, in particular the Internet. A bi-directional data connection via the Internet in both directions is enabled even across firewalls and starting from an OPC client, which is not visible as a server on the Internet. To achieve this, a first connection request for establishing a first transmission channel is sent from a first data processing device of an OPC client, via a data connection, to an OPC server of an automation system. The OPC server responds to the request using a second transmission channel. The data connection is thus kept open permanently, allowing data to be sent and received bi-permanently, allowing data to be sent and received bi-directionally, the operations being temporally independent of each other, between the OPC client and the OPC server by at least one data network, in particular, the Internet.

Abstract: OPC data is transmitted via data networks, in particular the Internet. A bi-directional data connection via the Internet in both directions, is enabled even across firewalls and starting from an OPC client, which is not visible as a server on the Internet. To achieve this, a first connection request for establishing a first transmission channel is sent from a first data processing device of an OPC client, via a data connection, to an OPC server of an automation system. The OPC server responds to the request using a second transmission channel. The data connection is thus kept open permanently, allowing data to be sent and received bi-permanently, allowing data to be sent and received bi-directionally, said operations being temporally independent of each other, between the OPC client and the OPC server by at least one data network, in particular, the Internet.

Abstract: The invention relates to a system and a method for transmitting data via data networks, especially via the Internet. The aim of the invention is to create a bi-directional data connection even behind firewalls, via Internet in both directions, including from a client (1) not visible as a server in the Internet. To this end, the invention provides a method or a system in which a first connection request for establishing a first transmission channel (6a, 7a, 8a) is sent to a server (4) of an automation system (5) from a first data processing device (1) of a client (1) via a data connection (6, 7, 8). This request is answered by the server (4) via a second transmission channel (6b, 7b, 8b). The data connection (6, 7, 8) is kept permanently open, hereby allowing mutually time-independent bi-directional sending and receiving of data between the client (1) and the server (4), via at least one data network, especially via the Internet.