Research On Key Technology Of RFID Middleware

RFID middleware technology, one of the core one of RFID technology, is very crucial to the development of RFID applications. Research of RFID middleware has currently made considerable progress abroad, putting forward the EPC global architecture standard for RFID applications. Based on this standard, many large-scale software companies have developed middleware products, which greatly facilitate the development of RFID application under the EPC system and now it is the mainstream technology of RFID middleware. In this paper, we study several key technologies of RFID middleware on the basis of EPC global architecture and achieve the following results:1 We conduct a study of the EPC global architecture and contrast the characteristics of several main RFID Middlewares. RFID middleware under the EPC global architecture works well, including tag data collection, processing, storage and sharing, so that the real large-scale RFID applications can be implemented. However, there exist some problems, of which the most serious one is the safety of access to tags. On the basis of the EPC global architecture, this paper proposes a SOA-based RFID middleware framework, under which some of the tight features are integrated as a service, and loose coupling is realized by communication interfaces among these services to increase the flexibility of system deployment. On the issue of tag-access security, the PKI mechanism is employed to enhance access security and the problem of its password exchange could be solved in circulation. In addition, it is recommended to strengthen the ability to manage these various devices with a dependent device management server.2 We do research into data processing algorithm of edge server in RFID. RFID Edge Server is the primary spot for raw data processing, where a large number of raw data from RFID devices are filtered, grouped and counted and form the initial event data of RFID application system. This paper proposes an improved T-Link tree index structure and the matching algorithm, which is fit to run in RFID edge server after a study of the laws of RFID data processing and T tree index structure of memory database. A comparison test between the T-Link tree algorithm and the general multi-link algorithm under a PC environment shows that the T-link tree algorithm performs better in the case of large amounts of data.3 Data relay through message-passing mechanisms in a RFID system, so it is very meaningful for RFID system to study security in message passing and rationality of query/subscribe mechanism. Since a large amount of data need to pass through the SOAP protocol in the RFID middleware framework presented here, this paper focuses on studying the SOAP-based message authentication and encryption security mechanism and analyzes the strengths and weaknesses. Afterwards, we advance a SOAP secure communication mechanism based on PKI- authentication and encryption technology, plus time-stamp technology, which could achieve higher security in message passing. At the same time, we present in detail the process of event publish, query and subscription in the architecture put forward, and provide query and subscription associated description of the agreement.4 Device management is another important issue needed to be resolved in RFID middleware. Due to the multiple devices with their own communication protocols and standards, it is necessary for RFID middleware to have the ability to integrate them in a single system. After we study on several mainstream methods of RFID middleware device management, we point out the faults existing respectively and then forward a self-management mechanism based on a device management server. A bottom virtual device interface (LLVDI) is firstly established on the basis of LLRP, through which data processing layer in edge servers operates all reading and writing equipment. Communication conversion layer of the edge server translates LLVDI into a specific device communication protocol according to a script written in reader device communication transformation language (RCPTL). For each type of this device, a RCPTL script is generated and placed on a centralized device management server. When the edge server finds a new device, it will ask the device management server for the appropriate protocol conversion script by protocol. In such a device management mechanism, it can achieve plug and play ability in network-wide as long as the device configuration protocol conversion scripts exist in the device management server.5 RFID tags access security is one of the most important issues needed to be solved in RFID application. EPC global standards regulated that they could only do KILL a tag or lock part of the contents on the tag with a password. This security mechanism has great limitations, because the symmetric cryptography encryption method makes it difficult to pass password in the course of open-loop logistics; Moreover, tag access password is sent in clear text format, which is easy to be wiretapped and results in safety issues. In view of problems on tag access, we propose a RFID encryption mechanism based on elliptic cryptography concerning the latest cryptography research. On account of asymmetric encryption technology employed, the problem of password passing is resolved in the case of open-loop logistics. Wireless wiretap is prohibited in the event of tag access, without Tag ID and access password in clear text format. With public and private keys, it is not only realistic for upstream companies to implement identification but also prohibitive for illegal downstream companies to carry out tag access. In view of the restrictions of current CMOS processing technology, non-symmetric encryption technology can not be applied to tags now, and we could expect to see that this mechanism would have practical significance in the near future as regards the laws of technological development.