1. A system for configuring a controller without file transfer, comprising: a processing unit; and a first memory connected to the processing unit; and wherein: a network variable configuration is situated in the first memory; the network variable configuration comprises a public variable identification (PVID); the public variable identification identifies a public variable whose value is written into a second memory of the processing unit; a replacement specification which also comprises a public variable identification, is read from the first memory; and values are written to a configuration file in a memory of a controller based on the instructions in the replacement specification.