An efficient signcryption scheme for vehicular satellite-based networks

With the widespread of the vehicular ad-hoc network (VANET), a huge number of vehicles are connecting to networks. To provide the position of these vehicles, the global position system (GPS) is required. Usually, the GPS is commoned with internal sensors mounted inside the vehicle. Thus, the communication with this sensor is needed when we need to specify the position of vehicle through the satellite. This communication is done by using a secure channels. However, the authentication and privacy are deemed as the main goal of the network communication. Therefore, an efficient signcryption scheme for vehicular satellite-based network (SVSN) is proposed in this paper. The proposed scheme meets the security demands for VANETs, for instance authentication, unforgeability, confidentiality, and integrity. Based on the Discrete Logarithm (DL) problem, the presented scheme is secure. Compared with the existing signcryption schemes, the performance analysis show that our proposed scheme is more suitable for vehicular satellite networks.

A Blockchain-Based Authentication Protocol Using Cryptocurrency Technology in LEO Satellite Networks

With the rapid development of satellite technology and the high transmission efficiency of LEO satellites, LEO satellite communication has received increasing attention. However, the frequent switching of satellite-earth links imposes a great challenge in LEO communication authentication. To tackle this challenge, this paper proposes a Blockchain-based Authentication Protocol Using Cryptocurrency Technology (BAPC), which solves the problem of a long pause time of satellite services caused by user access authentication in a scenario of frequent switching between satellites and ground users. First, we design three stages of the authentication process and introduce the cryptocurrency technology. Using currency transactions as the certificate of authentication improves not only the security of authentication, but also the efficiency of switching authentication. Next, in the network topology, the satellite cluster is divided into multiple regions to improve the efficiency of block consensus. Finally, the protocol is tested through extensive NS2-based simulations, and the results verify that BAPC can greatly shorten the response time of switching authentication and significantly reduce the time of block generation and the network throughput. As the number of users increases, the block generation time and network throughput can be further reduced.

A Review of Routing Algorithms Based on Multi-Layer Satellite Networks

Compared with single layer satellite network, satellite distribution of multi-layer satellite networks in the double layer or multilayer orbital plane, combines all the advantages of engaging subjects of the satellite, therefore contains its low vulnerability, good robustness, high stability, high spectrum efficiency and system throughput, channel characteristics such as large capacity, in the satellite network is a very promising direction. Multilayer satellite network also has some inevitable disadvantages, that is, the number of nodes and the number of links is large, so it has the characteristics of frequent changes in network topology, which requires higher routing algorithm. There are many researches on routing algorithms based on multi-layer satellite networks at home and abroad. This paper introduces the general situation of multi-layer satellite network, classifies the existing routing algorithms of multi-layer satellite network according to different standards, analyzes several typical routing algorithms in detail, points out the advantages and disadvantages, and summarizes the future development trend.

Ability of RTK-Based GPS Measurement Method in High Accuracy Work in Geomatics Study

Insfrastructure development require significant changes and transformation in Geomatics field for the upcoming decade. The use of new technology in Geomatics and surveying is essential and can be leveraged in many survey application that will help on building the nation towards a sustainable future. In the last 5 years, GNSS technology has been widely used and practiced to replace total station for survey work. Main factors that contributes to this busniness changes are the availability of much cheaper equipment with good technical capability in the market that helps surveyor to perform their work faster and more efficient. Global navigation satellite system services for accurate positioning has also rapidly increased and provide many option and solution for industry player or surveyor to choose. Combination of multiple global navigation satellite system providers such as GPS, GALILEO,GLONASS and BeiDOU has developed good satellite networks and increased numbers of available satellites for observation that improve absolute position accuracy. CHC i70 is among the best selling GNSS model on the market right now. The receiver can receive signal from GPS,GALILEO,GLONASS and BeiDOU simultaneously. This study will outline and focus on the capability of the RTK-Based method ( 30 second to 1 minute observation period) using CHC i70 instrument in high-precision measurement work. The research was done using the GPS calibration test site at Politeknik Sultan Haji Ahmad Shah (POLISAS) and was also practiced in the actual work for establishment of Temporary Bench Mark (TBM) along Jalan Melor to Ketereh, Kelantan. The result of the study found that RTK-Based method can meet the precision work that is permitted under 2cm accuracy. Studies show that the method of using RTK- Based is suitable for high precision work and improve the measurement time and work duration at field. Keywords : Beidou, Chc and RTK-Based GPS and PDOP