S E C U R I T Y
Licensing on Microcontrollers with Just a Few Kilobytes of Memory : Here ‘ s How !
More and more manufacturers from the industrial sector are asking us how they can use Wibu-Systems ’ license management solutions to protect the firmware or functionalities of small microcontrollers in the field . In this context , licensing is the primary focus . The key requirement for the licensing solution is minimal memory consumption – just a few kilobytes . To discuss this topic , the KEYnote editorial team spoke with Wibu-Systems ’ Embedded Product Manager ( PM ) and the microcontroller specialist from our Professional Services team ( PS ).
Editorial Team : Today , we ‘ re discussing how to bring the CodeMeter licensing solution to devices with such limited resources that even Code- Meter µ Embedded is too large . My question to the Embedded Product Manager : Where is such a solution needed , and who is using it ?
PM : Our industrial customers manufacture sensors and actuators in large quantities , such as frequency converters for motors , sensors for mechanical engineering , or valve controls in hydraulics . These devices require only minimal computing power but often contain high-value control algorithms or complex measurement functions . This software represents valuable intellectual property ( IP ) that needs protection . However , on these platforms , even the 64 KB of CodeMeter µ Embedded and the required RAM are too large to be implemented .
Editorial Team : Aren ‘ t microcontrollers becoming more powerful ? Many can now render web interfaces or communicate with the cloud .
PM : That ‘ s correct . For more powerful systems , CodeMeter Embedded is a great choice . However , let ‘ s take the example of a frequency converter used to control the speed of a servo motor . Here , the focus is on load monitoring , acceleration and braking ramps , and motor characteristics . Such devices operate with only a few kilobytes of RAM . The manufacturer , however , wants to license individual functions and control the number of devices produced at the contract manufacturer . These devices are produced in high volumes , and cost-sensitive component selection is crucial . A multifunctional security solution like CodeMeter simply doesn ‘ t fit within the limited memory available .
Editorial Team : How can a manufacturer still use the CodeMeter licensing concept ?
PM : With a specially adapted solution that optimally utilizes the available resources while ensuring a secure binding of the license to the hardware . At the same time , compatibility with
CodeMeter License Central and remote updates must be maintained . CodeMeter is highly flexible , allowing the necessary solution to be built from existing functions .
Editorial Team : The question goes to the developer : How does this work ? A CodeMeter licensing solution without CodeMeter Embedded ?
PS : We have developed a compact library for microcontrollers , reduced to the essential functions for license and signature verification , ensuring a minimal footprint . Additionally , we use an optimized license format specifically designed for resource-constrained microcontrollers . The license file is generated on a programming system using a host tool , derived from a regular CodeMeter license . This allows the entire CodeMeter ecosystem to remain fully functional while ensuring that the final license is securely bound to the target system . The host tool can be flexibly integrated into the
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