Limitations of the computational and energy capabilities of IoT devices provide new challenges in securing communication between devices. Physical layer security (PHYSEC) is one of the solutions that can be used to solve the communication security challenges. In this paper, we conducted an investigation on PHYSEC which utilizes channel reciprocity in generating a secret key, commonly known as secret key generation (SKG) schemes. Our research focused on the efforts to get a simple SKG scheme by eliminating the information reconciliation stage so as to reduce the high computational and communication cost. We exploited the pre-processing method by proposing a modified Kalman (MK) and performing a combination of the method with a multilevel quantization, i.e., combined multilevel quantization (CMQ). Our approach produces a simple SKG scheme for its significant increase in reciprocity so that an identical secret key between two legitimate users can be obtained without going through the information reconciliation stage.

Data sharing information regarding health status in the e-healthcare systems becomes one of private and very sensitive information that should be kept from exposure by illegal activities. However, since the information are exchanged across public networks (i.e., Internet and wireless networks), the information become vulnerable. Due to the participating users in the network can not be trusted, a secure data sharing process in the e-healthcare system would be mandatory. In this paper, we propose a secure data sharing in the e-healthcare system using Identity-Based Encryption (IBE) with signature to provide: (1) data sharing can be accessed by only authorized users based on unique public identity (ID) and kept its integrity from alteration during transmission simultaneously, and (2) data sharing are encrypted and authenticated such that the data can only be exchanged by authorized users. Meanwhile, experimental results are able to show the practicality of proposed system.

One solution to ensure secrecy in the Internet of Things (IoT) is cryptography. However, classical cryptographic systems require high computational complexity that is not appropriate for IoT devices with restricted computing resources, energy, and memory. Physical layer security that utilizes channel characteristics is an often used solution because it is simpler and more efficient than classical cryptographic systems. In this paper, we propose a signal strength exchange (SSE) system as an efficient key generation system and a synchronized quantization (SQ) method as a part of the SSE system that synchronizes data blocks in the quantization phase. The SQ method eliminates the signal pre-processing phase by performing a multi-bit conversion directly from the channel characteristics of the measurement results. Synchronization is carried out between the two authorized nodes to ensure sameness of the produced keys so it can eliminate the error-correcting phase. The test results at the IoT devices equipped with IEEE 802.11 radio show that SSE system is more efficient in terms of computing time and communication overhead than existing systems.

The school shuttle system commonly uses the vehicle to facilitate students to go and go home from school. However, there needs to be a development in terms of monitoring the students. In this paper explains the development of school shuttle system with IoT concept to apply Smart School application. The system will be designed uses a reader that will identify the identity card of students using Bluetooth Low Energy technology and a localization sensor to determine the position of the vehicle. Location information and passenger lists will be displayed in real-time mobile applications which are then accessed by parents. The results show that all we propose, In the system will use the algorithm selecting beacon node with rule based expert system approach, to select Cubeacon brought by students in the vehicle. From the testing results, Reader will select Cubeacon based on the algorithm used, with the restriction value RSSI -54 dBm. And the duration used is 1 minute to declare the student active or inactive in the vehicle.

The necessity for secured communication devices that has limited computing power has encouraged the development of key generation scheme. The generation of a symmetric key scheme that utilizes randomness of wireless channels offers a most promising solution as a result of the easy distribution of secret key mechanisms. In the last few years, various schemes have been proposed, but there are trade-offs between the performance parameters used. The expected parameters are the low Key Disagreement Rate (KDR), the high Key Generation Rate (KGR), and the fulfillment of standard of randomness. In this paper, we propose the use of a combination of pre-processing methods with multilevel lossy quantization to overcome the trade-off of performance parameters of the Secret Key Generation (SKG) scheme. Pre-process method used to improve reciprocity so as to reduce KDR, whereas multilevel quantization is used to improve the KGR. We use Kalman as the pre-processing method and Adaptive Quantization, Modified Multi-Bit (MMB), and 2-ary Quantization as the multilevel lossy quantization. Testing is conducted by comparing the performance between direct quantization with the addition of the pre-processing method in various multilevel lossy quantization schemes. The test results show that the use of Kalman as pre-processing methods and multilevel lossy quantization can overcome the trade-off performance parameters by reducing KDR and increasing KGR, with the best performance, was obtained when we use adaptive quantization. The resulting secret key has also fulfilled 6 random tests with p values greater than 0.01.

Shared key generation between two users to exploit the randomness of wireless channels as a source of secret key bits extraction has become an attractive alternative to ensure security in a mobile environment. In this paper, we evaluate the performance of key extraction scheme using measurement results of Received Signal Strength (RSS) on several variations of settings and types of movement. We add the moving average method before the quantization process so our scheme becomes more adaptive to the low variation of RSS, and the use of modified Level Crossing Algorithm to reduce Key Disagreement Rate (KDR) due to half-duplex mode, device limitation, and different types of devices. The results show that our proposed schemes, compared with the existing scheme produce bit stream with the highest entropy, a significant decrease of KDR and passed randomness test from NIST statistical suite.