| 摘要 |
<p>The invention relates to a method for maintaining field devices used for process automation technology by means of a maintenance computer (WS3, WS4) which is delivered by a device manufacturer, arranged in the company network LAN2 (Intranet) of the field device manufacturer and is connected to at least one of said field devices by means of said company network (LAN2), a public network (Internet) and a customer network LAN1 (Intranet). According to the inventive method, the public network is provided with a directory server in which a customer unit and the maintenance computer (WS3, WS4) are registered and which, upon the customer request, assigns a session identification number, selects the network address of a relay server (R) connected to the public network (I) and transmits said address to the customer unit and the maintenance computer (WS3, WS4). Said relay server (R) and the session identification number enable to set a pair-to-pair connection for data exchange about the field devices between the customer unit and the maintenance computer (WS3, WS4) in such a way that said pair-to-pair connection makes it possible to communicate by means of a firewall computer (FW1, FW2) which protects the customer network (LAN1) and the company network (LAN2) with respect to the public network (I).</p> |
