With the acceleration of global economic integration and information networking, in order to meet the requirements for the identification and efficient identification of a single item, the Auto ID laboratory of Massachusetts Institute of Technology (MIT), supported by the Uniform Code Council (UCC), proposed to build a system covering all things in the world on the basis of computer Internet, using RFID and wireless communication technology, At the same time, the concept of electronic product code (EPC) is proposed.
In other words, each object will be assigned a unique EPC, which will be managed and connected with each other by the information system using RFID technology: data transmission and data storage will be handled by the EPC network.
Subsequently, the European Association of Item Numbering (EAN) and the United States Uniform Code Association (UCC) jointly established EPC Global, a non-profit organization, in September 2003, which incorporated EPC into the global unified identification system, and achieved the perfect combination of GTIN (Global Trade Item Code) coding system and EPC concept in the global unified identification system.
EPC Global’s description of the Internet of Things is that an Internet of Things is mainly composed of EPC coding system, RFID system and EPC information network system.
1. EPC coding system
The Internet of Things realizes the real-time sharing of global goods information. Obviously, the first thing to do is to realize the unified coding of global goods, that is, to mark any product produced anywhere on the earth with an electronic label. This electronic tag carries an electronic product code, which is unique in the world. The electronic label represents the basic identification information of the article, such as “the E-piece of Class D product produced by Company A at time B and place C”. At present, EPC codes supported by Europe and America and UID codes supported by Japan are two common electronic product coding systems.
2. RFID system
RFID system includes EPC tag and reader writer. EPC label is the carrier of serial number (the unique number of each commodity, i.e. license plate). When EPC label is pasted on an article or embedded in an article, a one-to-one mapping relationship is established between the article and the product electronic code in EPC label.
EPC tag is essentially an electronic tag, and RFID reader can read the memory information in EPC tag. This memory information is usually the product electronic code. The product electronic code is reported to the Internet of Things middleware through the reader writer, and stored in the distributed database after processing.
The user can query the information of the item. In the address bar of the supply chain browser, enter the item name, manufacturer, supplier and other data to learn the status of the item in the supply chain in real time. At present, standards related to this part have also been formulated, including electronic label packaging standards and data interaction standards between electronic labels and readers.
3. EPC information network system
EPC information network system includes EPC middleware, EPC information discovery service and EPC information service (EPCIS).
1) EPC middleware
In order to realize the standardization of each small application environment or system and the communication between them, a common platform and interface must be set between the background application system and the reader writer, which is usually called middleware. EPC middleware is used to realize information interaction between RFID reader writer and background application system, capture real-time information and events, or upload to background application database system and ERP system, or downlink to RFID reader writer.
EPC middleware adopts standard protocols and interfaces, which is the link between RFID reader and information system. At present, the application level event (ALE) standard has been developed.
2) EPC information discovery service
EPC Information Discovery Service includes ONS and supporting services. It is based on EPC to obtain EPC data access channel information. At present, EPC Global has entrusted Verisign with the operation and maintenance of the root ONS system and the supporting discovery service system, and its standards are being formed;
3) EPC information service
The software support system of EPC system in EPC information service (EPCIS) is used to enable end users to interact with EPC information in the Internet of Things environment. The EPCIS interface and standard will provide a whole set of standard interfaces for EPC data. Once the EPCIS standard is recognized, it is very likely to promote the development of RFID industry, thus providing a standard way to capture and share the information business collected by the radio frequency word recognition chip.
The EPC IoT architecture is mainly composed of EPC code, EPC tag and RFID reader, Zhongtongyi system, ONS server and EPCIS server.
The basic framework of an enterprise Internet of Things application system consists of RFID identification system, middleware system and computer Internet system. Among them, RFID identification system includes EPC tag and RFID reader writer, which communicate through RFID air interface: EPC tag is attached to each item. The middleware system includes EPCIS, PML, ONS and their cache systems, and its background application database system also includes ERP systems; The middleware system is connected to the computer Internet, and can timely and effectively track, query, modify, or add or delete data.
To sum up, the EPC system is based on the computer Internet, through the EPC middleware, ONS and EPCIS to achieve the global interconnection of things.