Variable Length Encoding for Backward Channel Protection in RFID Systems

• Main Authors: Chih-Hung Lin, 林志鴻
• Other Authors: Robert Hsu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/96214082991567831031

碩士 === 中華大學 === 資訊工程學系(所) === 98 === RFID (Radio Frequency Identification) is a kind of communication technology that reader utilizes the wireless technology to identify the Tag data. In the recent years, RFID technology has been adopted in many application systems, such as supply chain management system, healthcare system, entrance control system, etc. Nowadays, there are many resources have been invested in the RFID research, which makes the RFID technology becomes more mature. As the wireless technology is adopted in RFID system to transfer the data between tag and reader, hence, the tag data will be eavesdropped easily should there be no encoding mechanism used in the data transmission between tag and reader. Therefore, the security issue is an extremely important objective and worth for discussion in RFID research. Consequently, a variable length encoding method (VLE) is proposed in this paper to improve the RFID security control. The VLE method adopts a simple encoding rule to improve the RFID security and protect data from being eavesdropped without adding loading in data transfer. In the VLE method, a new bit expression rule is adopted to identify data. In the new expression rule, each bit can express three data statuses; hence, data can be expressed with a shorter data length. The data expressed using the new data expression rule is called VLE Code. The VLE Code is passed from the tag to the reader and the reader will use a memory address and memory offset concepts to decode the tag data. This encoding and decoding method can achieve the objective of data protection with an easy and achievable way.