Experimental Analysis and implementation of Encryption in IEEE 802.11 Using GNU Radios

Abstract

Reliable and reproducible encryption mechanisms are essential in modern wireless communication systems, particularly when implementing IEEE 802.11 over software-defined radio (SDR) platforms. This paper presents an experimental framework that integrates Advanced Encryption Standard in Cipher Block Chaining mode (AES–CBC) with PKCS#7 padding into a GNU Radio based IEEE 802.11 transceiver using USRP B205mini‑i hardware. The system operates over 2.412 GHz and 5.89 GHz bands and supports multiple modulation and coding schemes (MCS), including BPSK, QPSK, 16QAM and 64QAM, enabling a comparative study of link robustness under low and high order modulations. Packet Reception Ratio (PRR) is formally defined and employed as the primary reliability metric, with PRR measured as a function of transmit gain and modulation order under controlled indoor conditions. A complete reference implementation of AES–CBC is provided, together with validation scripts, known-answer tests and interoperability checks against OpenSSL to ensure cryptographic correctness. Experimental results show that low‑order modulation, particularly BPSK with rate 1/2, achieves the most robust PRR performance, while higher order modulations exhibit sharper degradation with reduced link margin. The combined SDR–encryption testbed, along with shared code, test vectors and flowgraphs, offers a reproducible reference for future research on secure IEEE 802.11 implementations and can be extended to alternative cipher modes and adaptive link adaptation schemes.