Western Governors University (WGU) C839v5 / D334 Algorithms Practice Test

The Present cipher is a lightweight block cipher that is specifically designed for use in resource-constrained environments, such as RFID tags and IoT devices. The key sizes used in the Present cipher are typically 80 bits or 128 bits.

Choosing an 80-bit key allows for a balance between security and efficiency, making it suitable for applications where computational resources are limited. A 128-bit key provides a higher level of security, which is important for more sensitive applications, while still maintaining low resource requirements. Thus, the correct answer reflects the two common key sizes associated with the Present cipher effectively, emphasizing its design for security in minimal-resource situations.