Yan Xu Jie Zhang Xin Huang

摘 要：The Internet of Things （IoT） is a fast-growing industry that is bound to transform homes， cities and factories. Due to its broad influence in our life， IoT has grown exponentially in the last decade and appealed to researchers. Nowadays， during its rapid growth， IoT is facing with several challenges， of which the security issue is one of the biggest one. In this paper， we design a protocol with the help of Elliptic Curve Cryptography （ECC） to secure messages exchange. This protocol reduces the computational cost on the sensor node through transferring some heavy computing tasks to the coordinator. Finally， the implementation details of the protocol are presented.

關(guān)鍵詞：Internet of Things， Elliptic curve cryptography， authenticated key agreement.

I. INTRODUCTION

The Internet of things （IoT） is a new stage in the development of ubiquitous networks. Although IoT develops rapidly， it is inevitably associated with security issues. Especially in low-powerful nodes. In terms of [1]， small sensor nodes with the less processing capacity are applied in IoT increasingly. Meanwhile， Fadi et al. [2] notices the limitation in battery life， storage space and processing power of resource-limited sensor nodes. [3] points out that an adversary can impersonate the initiator， responder or initiate the man-in-the-middle attack. The initiator and responder have a false impression that they have a shared key. Nevertheless， each of them has a shared key with the attacker. Because of this， the communication security is vulnerable [4]. Furthermore， due to the limited battery and the limited processing power of sensor nodes， the computational burdens of sensors must be reduced [5].

This paper aims to secure the communication between sensor node and coordinator. Based on it， one security protocol is designed by using ECC algorithm. In our design， IoT establishes a secure link for Raspberry Pi and Laptop through this protocol.

II.IMPLEMENTATION

In this section， we carry out a set of experiments for the protocol to test the performance and system. These experiments were performed on Raspberry pi and PC. The HMAC function used for the experiments is SHA256. Five elliptic curves i.e. Curve P-192， P-224， P-256， P-384， P-521 are employed in our experiment. The PC is used as the monitor of Raspberry pi. We verify whether our protocol is useful when we carry them on the PC and Raspberry pi.

We run these five curves for ten times with each of them. Additionally， in order to observe the runtime of both sides more clearly， the average runtime of each elliptic curve is computed as shown in table 1：

According to the table 1， the runtime of the side on the sensor node is shorter than the runtime of the side on the coordinator. Therefore， we believe that shift the computational burden from sensor node to the coordinator is efficient to low-powerful sensors.

III.CONCLUSION

In this thesis， an improved protocol of IEEE 802.15.6 displayed authenticated association is designed. Our protocol realized the following aims of design： 1） Secure the communication between coordinator and sensor node. 2） Reduce the computing costs of the sensor node by shifting computational burden from sensor node to coordinator.

In the future， we plan to build a stronger network with other algorithms and add more sensor nodes to test our protocol.

REFERENCES

[1]Xue， N.， Liang， L.， Zhang， J.， & Huang， X. （2016， June）. An access control system for intelligent buildings. In Proceedings of the 9th EAI International Conference on Mobile Multimedia Communications （pp. 11-17）. ICST （Institute for Computer Sciences， Social-Informatics and Telecommunications Engineering）.

[2]Hamad， F.， Smalov， L.， & James， A. （2009）. Energy-aware Security in M-Commerce and the Internet of Things. IETE Technical review， 26（5）， 357-362.

[3]Huang， X.， Liu， D.， & Zhang， J. （2015， November）. An improved IEEE 802.15. 6 password authenticated association protocol. In Communications in China （ICCC）， 2015 IEEE/CIC International Conference on （pp. 1-5）. IEEE.

[4]Zhang， J.， Xue， N.， & Huang， X. （2016）. A Secure System for Pervasive Social Network-Based Healthcare. IEEE Access， 4， 9239-9250.

[5]Zhang， J.， Huang， X.， Craig， P.， Marshall， A.， & Liu， D. （2016）. An improved protocol for the password authenticated association of IEEE 802.15. 6 standard that alleviates computational burden on the node. Symmetry， 8（11）， 131..