EPC coding is a new generation coding standard compatible with EAN.UCC coding. In EPC system, EPC coding is combined with the current GTIN. Therefore, EPC does not replace the current bar code standard, but gradually transitions from the current bar code standard to the EPC standard or It is the coexistence of EPC and EAN.UCC systems in the future supply chain. EPC is the only information stored in radio frequency tags and has been supported by the main oversight bodies of the two international standards of UCC and International EAN. The goal of EPC is to provide a unique identifier for objects in the physical world. It identifies and accesses individual objects through a computer network, just as it uses IP addresses to identify, organize, and communicate on the Internet. The following is a brief introduction to the coding scheme of the electronic code of the product.


First, the characteristics of EPC coding:

1. Unique Identification
Unlike the currently widely used EAN.UCC code, the EPC provides a unique identification of physical objects. In other words, an EPC code is assigned to one and only one item is used.

2. Embedded Information
Whether or not to embed information in the EPC has been controversial. Current coding standards, such as the UCC/EAN-128 Application Identifier (AI), contain data. Such information may include, for example, the weight, size, expiration date, destination, etc. of the item.
The AUTO-ID Center recommends eliminating or minimizing the amount of information embedded in the EPC code. The basic idea is to use the existing computer network and current information resources to store data, so that EPC becomes a reference for information, has the smallest amount of information, and of course needs to be balanced with actual requirements, such as easy to use, and system. Compatible and so on. Regardless of whether information is stored in the EPC, the goal of the AUTO-ID Center is to identify physical objects. According to this principle, the definition EPC is part of a coding scheme that uniquely identifies trade items.

3. Reference Information (Information Reference)
The primary role of the product electronic code is as a reference for network information. In other words, EPC is essentially an "indicator" of online data. A common reference for using the Internet is the Uniform Resource Identifier (URI), which includes the previous Uniform Resource Locator (URL) and Uniform Resource Name (URN). These identifiers are translated by the Domain Name Service (DNS) into the relevant network protocol (IP) addresses, which are the addresses of the network information. Similarly, the Object Name Resolution Service (ONS) provided by the AUTO-ID Center translates the EPC code directly into an IP address. The background of the IP address identifier stores the relevant product information, and then the host identified by the IP address will send information about the stored product. ONS is essentially equivalent to the "glue" between EPC encoding and network information. Therefore, the structure of the encoding should facilitate the search of the host address and improve the efficiency of the search by the object "yellow page".
 
Second, the structure of EPC coding

The EPC code is a set of numbers consisting of a version number and three other pieces of data (in turn, domain name management, object type, serial number). The version number identifies the version number of the EPC, which allows the later EPCs to have different lengths or types; the domain name management is information describing the manufacturer associated with the EPC, such as "Coca-Cola Company"; the object type records the exact type of information of the product. For example: "The 330ml canned slimming cola produced in the United States (a new product of Coca-Cola)"; the serial number uniquely identifies the goods, and it will tell us exactly which jar of 330ml canned slimming cola. Up to now, EPC-96I type, EPC-64I type, II type, III type, EPC-256I type, II type, III type and other coding schemes have been introduced.

The figure below shows the coding structure of the EPC-96I type:

Third, the conclusion

The EPC goal is to provide a unique identifier for all entities, in addition to physical entities, can also be used to identify non-physical entities such as services, organizations, and so on. It identifies and accesses individual objects through a computer network, just as it uses IP addresses to identify, organize, and communicate on the Internet. In the EPC coding design, there has been such a misunderstanding that the more functions of the EPC tag, the better, and the more information embedded in it, the better. This will inevitably increase the size of the label and increase the cost, which is not conducive to its promotion. Therefore, the Automated Identification Technology Lab proposes a solution that puts more information on the network, and the EPC only provides a search number for the information.

The Automated Identification Lab is currently designing, building, testing, and deploying a global infrastructure—a layer of communications that overlays the Internet. It allows the computer to recognize any object in real time anywhere in the world, known as the Internet of Things. The network not only provides a way to pass reliable, accurate, and real-time information back to existing business applications, but it also brings a new era of innovation and opportunity. This will be the next network revolution.