Research on information security technology of Internet of Things

Core tips:According to the 2012 22nd issue of Silicon Valley magazine, the application of the Internet of things in various fields has also extended the original cyber security threat to the physical world, increasing the difficulty of prevention and management, according to the three levels of the internet of things, analyzing the security characteristics of IoT, especially the security of perceptual layer, And the key management technology in the Internet of things security technology into ...

The Internet of Things (IoT) is a vast network of information-sensing devices, such as radio frequency identification (RFID), infrared sensors, global positioning systems, laser scanners, and other information-sensing devices, based on computer networks, to communicate and communicate information to achieve the identification, tracking, Positioning and management, i.e. "internetofthings". It is the main direction of the next network development, with a comprehensive sense, reliable transmission, intelligent processing characteristics. So IoT is the Internet, sensor network, mobile network, such as the integration of a variety of networks, users driven by the original people to expand to any of the objects can be exchanged between the communication and information. However, with the integration of these networks and the re-formation of a unified new network, so that network intrusion, virus transmission and other factors that affect the scope of security more and more, it has a variety of network existing security problems, but also has its own particularity, such as privacy issues, authentication between different networks, reliable transmission of information, Big data processing and other new problems will be more serious. Therefore, in the development of the Internet of things, we must pay attention to the problems of network security, formulate unified planning and standards, establish a complete security system, and maintain healthy and sustainable development.

1 security features of the Internet of things
The Internet of things is divided into three levels according to General standards: Application layer, network layer, perceptual layer. The application layer is mainly computer terminal, database server and so on, carries on the data reception, the analysis and the processing, orders to the other terminal of the perceptual system. The network layer relies on existing networks, such as the Internet and mobile networks, to transmit the communication data between the application layer and the perceptual layer safely and reliably, similar to the human nervous system. The perceptual layer mainly includes some wireless sensor devices, RFID tags and readers, status sensors, etc., similar to the body's senses. Although each layer has a strong password technology and security measures, but independent security measures can not be a multi-layered integration of the new huge IoT system to solve security problems, so we must on the original basis to study the system after the integration of new security issues.

Application layer support IoT business has different strategies, such as cloud computing, distributed systems, big data processing and so on for the corresponding service applications to establish an efficient, reliable, stable system, this multi-service type, multiple platforms, large-scale IoT systems are facing the establishment of security architecture issues.

Although the network layer has certain security protection ability on the foundation of the Internet, but in the IoT system, because of the large increase of the client node, the information node also expands from the original person to the object to communicate, the amount of data increases sharply, how to adapt to the transmission of perceptual information, and the confidentiality of information, Integrity and availability guarantee that the privacy of information, information encryption in the multi-heterogeneous Internet of things is more difficult.

Perceptual layer information collection, aggregation, integration, transmission and information security issues, because the internet of things sense of the complexity of the network, all areas are likely to be involved in the relative diversity of perceptual nodes, sensor function is simple, can not have a complex security protection ability.

2 security issues with perceptual layers
As the application layer and the network layer are relatively familiar to us, and the perceptual layer is the most embodiment of the internet of things in the internet of things, information security is relatively weak agenda, we understand the perception layer of security issues.

The perceptual layer collects the information from the terminal node mainly through various kinds of sensors and equipment, uses the sensor to identify the object, can complete some complicated operation wirelessly or remotely, and save the manpower cost. In the Internet of things, most of these sensors or devices are installed in some unattended locations, which can be easily contacted or destroyed, easily disturbed, or even difficult to operate properly, or illegally controlled by criminals.

For example, we in the internet of Things common RFID system, it is mainly designed to improve efficiency, reduce costs, due to the limitations of the label cost, it is difficult to adopt a strong encryption method. and its labels and readers take a wireless contactless approach and are vulnerable to interception, leading to serious security threats during data collection, transmission, and processing. RFID system is generally deployed in outdoor environment, vulnerable to external influences, such as signal interference, due to the current frequency of electromagnetic waves in each band in use, interference between the signal is large, it may lead to error reading commands, resulting in state confusion, the reader does not recognize the correct label information; illegally copying labels, Impersonating other tags to send information to the reader, illegal access, tampering with the contents of the label, this is because most of the tags in order to control the cost is not a strong encryption mechanism, most of them are not encrypted processing, the corresponding information is easy to read illegally, resulting in illegal tracking or even modify data, by interfering with the RF system, network attack, affect the operation of the entire network.

For this we should take the security measures: first of all the information passed between the label and the reader authentication or encryption, including password authentication, digital signature, hash lock, two-way authentication or third-party authentication and other technologies, to ensure that the reader to decrypt the data before the label information is locked; second, to establish a dedicated communication protocol , through the use of automatic channel selection, electromagnetic shielding and channel scrambling technology to reduce interference to avoid attack, but also through the coding technology to verify the integrity of the information to improve anti-jamming ability, or through the multiple sending of information to check error correction.

So for the security threat of perceptual layer, we need to establish an effective key management system, a reasonable security architecture, and a special communication protocol to ensure the security, reliability and stability of the perceptual layer information.

3 Key Management technology for Internet of things
Key management in the Internet of Things is one of the powerful guarantee means to realize information security, we should establish a unified key management system involving multiple networks, and solve the problems of the allocation, updating and multicast of perceptual layer keys. All of this is built on the basis of encryption technology, through encryption to achieve integrity, confidentiality and non-repudiation of the requirements. Encryption technology is divided into two parts: Algorithms and Keys. Before the more mature international algorithms have aes,des and so on, at the same time they need a strong key generation algorithm to ensure the security of information.

At present, key management technology is mainly divided into symmetric key management and asymmetric key management, and symmetric key management is divided into pre-distribution, central mode and cluster-clustering method. Compared with asymmetric key system, the computational complexity of the Q-composite key preset method, probabilistic key pre-allocation method, spins protocol, e-g method, etc. is relatively low, but the security is relatively low. Asymmetric Key Management is a typical ECC public key cryptography system, its hardware implementation is simple, in the same intensity of large integer domain, its computational and storage complexity has a great advantage, on ECC, multiplication and addition operations faster, but the pairing operation is slow.

ECC is a typical elliptic curve based discrete logarithm problem, compared with the traditional encryption algorithm, it has the characteristics of high security, small computational capacity, fast processing speed, small storage space and low bandwidth requirement. Because of the difficulty of calculating the discrete logarithm of the point group on ECC Elliptic curve, it is pointed out that the complexity of the computation time is different, which determines its anti-attack strength is very high. Under the same resource condition, ECC is much faster than other encryption algorithms at encryption speed, because the key generation speed of ECC system is more than that of traditional encryption algorithm, so its encryption performance is obviously higher. At the same time, the key size of ECC is much smaller than the traditional encryption algorithm, but it has the same security intensity, so it means that ECC occupies a much smaller storage space, which is very important for the use of secret algorithm in IoT system under the influence of resource environment constraints. In the case of long message encryption and decryption, the traditional algorithm and ECC have a certain demand for bandwidth, basically at the same level, but in the short message encryption and decryption, the requirements of ECC is significantly lower, so ECC in the wireless network environment for the application has a great advantage.

In the key management technology of the Internet of things, whether it is symmetric key management or asymmetric key management, it is necessary to solve the problems in the Internet of things system to reduce the reliance of high-level information security on various operations, improve the security of Internet of things information and reduce the security cost.

4 Conclusion
IoT security technology is critical to the future of IoT in all areas, and because of the heterogeneous nature of information in IoT systems, the security situation for the Internet of things will be even tougher. In particular, the security research of perceptual layer needs to be strengthened, and how to establish an effective security architecture spanning multiple networks makes one of our research emphases. In the aspect of key management, how to improve the efficiency of the encryption algorithm and improve the performance of the sensor need us to study deeply. At the same time, we also need to establish and perfect a unified security technology standards, certification mechanisms, mature security and security system in order to deal with the development of the Internet of things in the face of the challenges.

Research on information security technology of Internet of Things (turn)