Implementasi Lightweight Cryptography Ascon dan Elliptic Curve Diffie-Hellman (ECDH) pada Mekanisme Transmisi Data LoRa

Abstract

Pertumbuhan volume data yang pesat mendorong kebutuhan sistem transmisi data yang efektif dan aman, khususnya pada pertanian cerdas (smart agriculture) yang umumnya berada di kawasan dengan infrastruktur jaringan terbatas (tidak terjangkau jaringan konvensional). Teknologi Long Range (LoRa) menawarkan solusi transmisi data jarak jauh (2-20 km), laju data rendah (0,3-50 kbps) dengan konsumsi daya rendah dan ukuran payload kecil (51-222 bytes). Namun demikian, komunikasi LoRa point-to-point (P2P) tidak memiliki mekanisme keamanan bawaan sehingga rentan terhadap serangan. Penelitian ini bertujuan mengimplementasikan algoritme kriptografi ringan Ascon yang dikombinasikan dengan Elliptic Curve Diffie-Hellman (ECDH) sebagai metode pertukaran kunci dinamis pada topologi many-to-one. Kunci sesi yang dibangkitkan secara dinamis melalui ECDH dan diautentikasi menggunakan Pre-Shared Key (PSK) statis digunakan oleh Ascon untuk menjamin kerahasiaan, integritas, dan autentisitas data sensor sintetis DHT11. Keamanan sistem dievaluasi melalui simulasi serangan eavesdropping, data injection, replay attack, man-in-the-middle (MitM), serta pengujian forward secrecy. Kinerjanya dievaluasi berdasarkan latensi, penggunaan CPU, penggunaan memori (RAM heap), overhead handshake, dan packet delivery ratio (PDR). Hasil pengujian menunjukkan skema usulan memenuhi seluruh kebutuhan keamanan, yaitu kerahasiaan, integritas, autentisitas, ketahanan replay dan MitM, serta forward secrecy, yang tidak seluruhnya dipenuhi skema plaintext maupun PSK statis. Dari sisi kinerja, Ascon-128 lebih hemat daripada AES-128 GCM pada payload kecil dengan dekripsi 25.273 siklus dibanding 38.631 siklus, sementara PDR pada topologi many-to-one setara di kisaran 90–91%. Dengan demikian, kombinasi Ascon-128 dan ECDH mampu meningkatkan keamanan transmisi LoRa P2P tanpa mengorbankan efisiensi.

The rapid growth in data volume is driving the need for effective and secure data transmission systems, particularly in smart agriculture, which is generally located in areas with limited network infrastructure (where conventional networks are not available). Long Range (LoRa) technology offers a solution for long-range data transmission (2–20 km) at low data rates (0.3–50 kbps) with low power consumption and small payload sizes (51–222 bytes). However, point-to-point (P2P) LoRa communication lacks built-in security mechanisms, making it vulnerable to attacks. This research aims to implement the lightweight Ascon cryptographic algorithm combined with Elliptic Curve Diffie-Hellman (ECDH) as a dynamic key exchange method in a many-to-one topology. Session keys dynamically generated via ECDH and authenticated using a static Pre-Shared Key (PSK) are utilized by Ascon to ensure the confidentiality, integrity, and authenticity of data from the DHT11 synthetic sensor. System security was evaluated through simulations of eavesdropping, data injection, replay attacks, man-in-the-middle (MitM) attacks, and forward secrecy testing. Performance was evaluated based on latency, CPU usage, memory usage (RAM heap), handshake overhead, and packet delivery ratio (PDR). The test results show that the proposed scheme meets all security requirements, namely, confidentiality, integrity, authenticity, resistance to replay and MitM attacks, and forward secrecy which are not fully met by either the plaintext scheme or the static PSK scheme. In terms of performance, Ascon-128 is more efficient than AES-128-GCM for small payloads, requiring 25,273 cycles for decryption compared to 38,631 cycles, while the PDR in a many-to-one topology is comparable at around 90–91%. Thus, the combination of Ascon-128 and ECDH enhances the security of LoRa P2P transmissions without sacrificing efficiency.