If access to automation applications is required for remote maintenance purposes, internal company firewalls are an obstacle for the external service, and the Codesys PLC CPM 20 from MKT offers a solution, which can establish encrypted connections independently and thus allows uncomplicated, secure access to the respective applications. As an option, the company offers a 'WebVisu' function with which all visualization masks created with Codesys can be opened in regular web browsers. The small controller uses openVPN to set up the VPN tunnel to the service location. External routers do not need to be configured. The small controller includes Ethercat master and CANopen master/slave. At the heart of the PLC is an ARM11 processor with a 532 MHz clock rate. The controller also has up to 64 MByte NOR flash, 64 KByte FRAM, optional 1 Gbyte NAND flash and is available with 128 or 256 MByte DDR2 SDRAM. The housing achieves protection class IP20.