GFRX: A New Lightweight Block Cipher for Resource-Constrained IoT Nodes

The study of lightweight block ciphers has been a “hot topic”. As one the main structures ciphers, Feistel structure attracted much attention. However, traditional cipher changes only half plaintext in an iterative round, resulting slow diffusion. Therefore, more encryption rounds are required to ensure security. To address this issue, new algorithm, GFRX, is proposed, which combines generalized and ARX (Addition or AND, Rotation, XOR). GFRX algorithm uses with different non-linear components deal all branches so that it can achieve better diffusion effect fewer rounds. results security analysis show effective differential attacks do not exceed 19 linear 13 adequate level for analysis. Avalanche test obtained strong takes six meet avalanche effect. In addition, serialization levels depending on hardware resource requirements full serialization, ensures operational flexibility resource-constrained environments.