1. Digital Village
The research on smart villages and smart cities stems from the concept of “Smart Earth” proposed by IBM in 2008. The research on smart cities has received much attention from academia, but smart villages are still a rising topic in academia.
Due to the vagueness of the concepts of the smart city and the digital city, they are regarded as the same concept and are often used interchangeably 
. Through a bibliometric analysis, Mora et al., (2019) believe that smart cities and digital cities share some common characteristics, such as focusing on urban ICT infrastructure and services 
. Nevertheless, smart cities are the framework in which technology, policy and community affect urban liveability, sustainability, governance, productivity, wellbeing and accessibility 
. Therefore, smart cities involve more extensive aspects than digital cities, which are part of smart cities.
Smart villages are the result of the expansion of the concept of smart development from cities to rural areas, and there are both links and differences between smart villages and smart cities. The deep integration of information technology and digital technology with the economic, ecological, social and cultural fields is the common element of both. Nevertheless, compared with cities, rural areas have weak infrastructure and are subject to more substantial resource constraints, farmers are generally less educated, and rural aging and population loss are very serious 
. In this context, the construction focus of smart villages is different from that of smart cities, and the construction difficulty of smart villages will increase. Therefore, the smart village does not simply apply the technologies involved in the smart city construction to the rural construction 
It is difficult to have a uniform definition of a smart village because of the differences in the environment and the problems faced by each village 
. The most widely cited definition is proposed by the EU Smart Village Initiative, launched by the European Commission. Smart villages combine the advantages of the village itself with digital, telecommunication technology, innovation and a better use of knowledge to benefit residents and businesses through network services 
. The Chinese government proposes that the digital village is an endogenous rural development process, accompanied by the application of networking, informatization and digitization in rural areas and the improvement of farmers’ modern information skills 
. It can be seen that the digital countryside proposed by China is essentially the same as the smart countryside proposed by the EU, except that Chinese practice and research often choose the term “digital village” due to policy orientation.
Up to now, the digital village has attracted worldwide attention, and some countries and regions have begun to carry out digital village construction activities. India launched the Digital India Program in July 2015, to transform India from a traditional society to a digitally empowered and knowledge-based society. As an important part of the entire project, the Digital Village initiative aims to increase the rural Internet penetration by building fiber-optic networks 
. To address the large urban-rural digital divide and rural exodus, South Korea launched the Information Network Village Project in 2001. The project aims to improve farmers’ incomes by training farmers’ skills, based on infrastructure development, and the project mainly involves network access, digital training, telemedicine, and digital agriculture 
. The EU proposed the Smart Villages campaign in 2017, which aims to revitalize rural areas by accelerating the rural development by digitalization and improving farmers’ quality of life. The campaign involves 16 plans, including sustainable development of the residents’ livelihoods, rural industries and public services. Under the framework of the Smart Villages campaign, Italy, France, Poland and other countries have launched different digital village construction plans, according to their own conditions 
. Moreover, the EU launched a two-and-a-half-year Smart Rural 21 project, in 2019, to select 21 villages for financial and technical support, and eventually promote the smart rural construction experience of 21 villages within the EU. Stojanova et al., (2021) analyzed the digital village construction policies of six countries in the EU, and found that digital village construction aims to solve the problem of the rural population reduction and population aging, climate change, economic development, infrastructure and services, digital transformation and narrowing the gap between urban and rural areas. However, there are differences in the degree of policy attention in different aspects 
From the content of the above digital village construction projects in each country, it can be concluded that the focus of the digital village construction differs from country to country. Due to the poor infrastructure in India, it focuses on the construction and improvement of digital technology facilities. The digital technology facilities in European countries are relatively complete, and their project construction scope is more comprehensive, mainly through the use of new technologies and the improvement of public services to improve the rural development environment. Because of the differences between the environment in China and other countries, and the significant differences among the regions within China, the construction of digital villages in China is more complex, but there is a lack of theoretical research papers for the Chinese context. Although Zhang and Zhang have proposed a framework for the Chinese digital village construction, based on complex system theory 
, but does not conduct an in-depth analysis of the Chinese digital village practice cases. At the same time, the most current studies focus on the developmental origin and concept definition of digital villages, the significance of digital village construction, and the policy interpretation of the digital village strategies in various countries, lacking in-depth exploration of the content and construction logic of the digital village construction.
2. The Digital Village Technology Architecture System
The digital village is the deep integration of digital technology and the village, and it is an inevitable choice for the village to adapt to the development of the digital economy era. The digital village construction involves a wide range of fields, and the current mature construction mode is to pilot in a specific field first, and then spread to other fields. However, there are differences in digital technologies in different fields, and if there is a lack of unified construction planning, it is easy to duplicate the construction phenomenon and reduce the positive impact brought by the digital village construction. At present, digital village construction has been carried out in some areas of China, but the results are quite different, and the lack of planned repetitive construction is one of the main reasons for the difference. Therefore, it is necessary to clarify the technical architecture system for construction before implementing digital village projects. All construction contents should be carried out under the guidance of the technical architecture system, which is conducive to unified planning and reduced economic costs caused by redundant construction.
As shown in Figure 1, the digital village technology architecture system constructed here is divided into four levels: infrastructure system, village brain, application support system and application service system. A complete digital village construction needs to include these four levels. The differences in construction in different fields are mainly concentrated in the level of the application service system, while the specific construction content of the other three levels needs to be matched, according to the needs of application development.
Figure 1. The digital village technology architecture system.
3. Infrastructure System
The infrastructure system consists of three parts: IoT perception, communication transmission network and computing services. IoT perception is the front-end of the digital village construction, which realizes data collection, intelligent identification and three-dimensional perception through sensing devices, remote sensing satellites, unmanned aerial vehicles (UAVs), intelligent terminals, video monitoring and weather stations. The communication transmission network is to upload the collected data to the data center efficiently and safely, mainly including wired networks, wireless networks and visual networking. Villages need to set up different types of networks, according to their actual conditions. Computing service is to provide computing power support for the development of various applications through the real-time processing of data. During the construction process, it is necessary to select computing services that match the hardware equipment, according to the server’s computing power and the memory’s storage capacity. The computing services mainly include cloud computing, edge computing, fog computing and haze computing.
4. Village Brain
Village Brain builds the digital platforms by adopting digital technologies, such as big data, blockchains and artificial intelligence, to support the digital transformation of rural decision-making and the automation of business processes.
The IoT perception platform mainly manages the data collected by the IoT in a unified manner, and uses visualization technology to display the data intuitively, promoting the formation of rural big data and providing a basic perception data guarantee for the subsequent application development.
Through intelligent analysis technologies, such as face recognition and license plate recognition, the visual networking platform can extract valuable information from massive videos, realize intelligent analysis and judgment, and lay the foundation for subsequent application, management and model innovation. In this process, the video network platform should pay attention to formulating video monitoring standards to support the sharing of various video monitoring resources effectively.
The big data platform mainly uses tools, such as data sharing and exchange, data management, data development and big data resource pools to break down industry data barriers, realize the integration and sharing of various heterogeneous data and promote the transformation of data resources into data assets.
The digital twin platform uses tools, such as the geographic information system (GIS), building information modeling (BIM) system and decision analysis applications, to realize the integrated display of basic geographic information, perception information and industry application scenarios through 3D modeling. Specifically, the digital twin platform uses digital technology to render the scene to restore the real physical world as much as possible. Moreover, simulation and evolution in digital space can provide prediction guidance for decision-making in the real physical space, reducing the economic cost and negative impact of attempts in real space.
5. Application Support System
The application support system connects the two important structures of the rural brain and the application service system through the application of integration services, mobile support services, toolset services and data interfaces. The upper application development can enjoy the efficient and friendly development and runtime environment in the application support system, realizing the rapid switch between cooperation and independent operation and providing support for personalized application development.
6. Application Service System
Combined with the digital village’s construction content and the rural sustainable development goal, the application service system can be divided into five aspects: industrial development, ecological livability, cultural prosperity, service improvement and efficient governance.
Industrial development is the combination of big data, IoT, artificial intelligence and other technologies, with agricultural production and operation activities, through intelligent decision-making and intelligent early warning to improve agricultural production efficiency and product quality, and finally to improve the effective supply of agricultural products and services. The construction content mainly includes smart agriculture, rural e-commerce, smart tourism, digital inclusive finance, and agricultural socialization services.
Ecological livability is using digital technology to improve the ecological environment and provide a basis for improving the rural living environment. The construction content mainly involves water source monitoring, air quality monitoring, toilet revolution, ecological energy and the intelligent control of green spaces.
Cultural prosperity is using digital technology to introduce external culture into the rural area, while accelerating the inheritance, innovation and dissemination of rural culture. The construction content mainly contains digital museums, rural cultural propaganda, rural network cultural guidance, digital libraries and village panoramas.
Service improvement is to use digital technology to facilitate the digital transformation of rural services, improve existing service levels and create new service models. The construction content mainly includes internet education, internet medical care, wisdom pension, consumer goods to the countryside and convenience services.
Efficient governance is the use of digital means to deal with all aspects of rural production and life affairs, and to improve the scientific nature of rural governance. The construction content mainly involves village affairs management, smart party building, peaceful village, villagers’ autonomy and emergency management.