This thesis focuses on specific crypto algorithms, Message Authentication Codes (MACs), running on ultra-low SWaP devices. The type of MACs we used is hash-based message authentication codes (HMAC) and cipher-block-chaining message authentication code (CBC-MAC). The most important thing about ultra-low SWaP devices is their energy usage. This thesis measures different implementations' execution times on ultra-low SWaP devices. We could understand which implementation is suitable for a specific device. In order to understand the crypto algorithm we used, this thesis briefly introduces the concept of hash-based message authentication codes (HMAC) and cipher-block-chaining message authentication code (CBC-MAC) from a high level, including their usage and advantage. The research method is empirical research. This thesis determines the execution times of different implementations. These two algorithms (HMAC and CBC-MAC) contain three implementations. The result comes from those implementations running on the devices we used. / Master of Science / The deployments of 5G cellular networks are now onboard. The demand increased due to consumers and the availability of more affordable devices. The amount of investment in 5G technology and infrastructure increases market interest in IoT. The 5G network security is essential. How to secure user privacy and their sensitive data while they use 5g network has become a big issue and needs to be solved. However, not all popular crypto algorithms are suited to all devices, especially in those resource-limited microcontrollers. In this thesis, we will deal with Message Authentication Codes that provide the data integrity check. With resource limit devices, energy usage is an important issue. We will identify which implementations have better energy usage depending on the device features. This thesis will use three implementations for each algorithm. The result of our experiment provide a straightforward way that helps people understand which implementation can run more efficiently on specific ultra-low devices.