Vigenere Cipher Cryptography for Secure Data Transmission in IoT Smart Door Using QR Code

Riski Arasyid — 2026-04-01

The Smart Door system based on the Internet of Things (IoT) using QR Code offers automated access but remains vulnerable to data sniffing attacks. This study implements the Vigenère Cipher algorithm to encrypt transmitted data and analyzes the ciphertext's resistance to attacks as well as its impact on communication delay. The system is built using ESP32-CAM as the QR scanner and NodeMCU ESP32 as the main controller, with encryption applied across three communication paths: ESP32-CAM to server, server to database, and server to ESP32. Testing involved data sniffing, delay analysis, and ciphertext evaluation using tools such as dCode and CryptoTool. From 20 sniffed QR Code results, 10 random samples were tested, and only 3 were recognized as Vigenère Cipher and none were decrypted successfully. In the server-to-ESP32 path, only 1 out of 10 ciphertexts was detected and all remained undeciphered. The average delay was recorded at 2.473 seconds (door unlocking) and 3.491 seconds (buzzer activation), with variations due to network stability. The results indicate that Vigenère Cipher effectively enhances data security in resource-constrained IoT devices, although delay optimization is needed to meet real-time system requirements.

Assessment of Internet Service Quality on Campus and Its Impact on Student Satisfaction

Ahmad Faris Al Faridzin — 2026-06-07

Internet service quality plays an important role in supporting digital-based academic activities in higher education, including online learning, access to scientific journals, and academic communication. However, students still frequently experience network problems such as slow and unstable connections, high latency, jitter, and packet loss, which may affect the effectiveness of the learning process. This study aims to evaluate the quality of campus internet services based on Quality of Service (QoS) parameters and analyze their relationship with student satisfaction toward campus internet services. The study employed a quantitative approach using observation and survey methods. QoS measurements were conducted using Speedtest and Pingtest at several campus locations during peak and non-peak hours, while student satisfaction data were collected through an online survey involving 120 respondents. The data were analyzed using descriptive analysis and Pearson correlation analysis. The results showed that internet network quality decreased during peak hours, indicated by lower internet speed and higher latency, jitter, and packet loss. The survey results also revealed that most students were still dissatisfied with the quality of campus internet services. Correlation analysis indicated that internet speed had a positive relationship with student satisfaction, while latency, jitter, and packet loss had negative relationships with user satisfaction levels. Based on the findings, increasing bandwidth capacity, adding Wi-Fi access points, and conducting regular network maintenance are necessary to improve the quality of campus internet services.

Jurnal Media Informasi Teknologi

Vigenere Cipher Cryptography for Secure Data Transmission in IoT Smart Door Using QR Code

Assessment of Internet Service Quality on Campus and Its Impact on Student Satisfaction