challenges and prospects

Considerations in aggregation #

In order to build a practical, correct content and stable aggregation project and avoid disputes over rights and interests, the following matters need to be paid attention to when developing and designing the project.

• Quality and applicability of Web resources: Without a strict administrator on the Internet, anyone can publish geographical information on the Internet, and the quality of these Web resources varies. If some information that is not completely correct or applicable is used in the aggregation chain, these errors and uncertainties will spread and amplify on the Internet, leading to wrong conclusions and decisions. In aggregation applications, you should select appropriate Web resources, pay attention to the authority of the information source, and pay attention to understanding how the data source is processed and updated (see Section 7.4.1).

• Extensibility of Web resources: Aggregations and their Web resources interact. On the one hand, the stability of its system depends on the stability of its resource providers; on the other hand, it will add load to its Web resources. For example, if a service A is called by 10 aggregations, if each aggregation accepts 50 clicks per minute, then Web page A may withstand (100x5 =) 500 more clicks, which may exceed the design capacity of Web service A, overwhelm Service A, and then cause all aggregations based on Service A to fail to function properly. This requires developers to choose Web resources with better scalability as much as possible, such as services provided by large cloud GIS centers. If the information source system you choose is not highly scalable, developers need to reduce the frequency of resource calls (e.g., changing from once per minute to once every five minutes).

• Copyright and terms of use for Web resources: Although openness and free are still the mainstream of the Internet spirit, many websites and free GIS clouds have some varying degrees of copyright protection and use restrictions. These terms may include limits on the amount of data access, limits on the number of requests per day, and statements that the terms may change in the future (e.g., from free to charged, and possible insertion of advertisements in information sources in the future). Issues of copyright and terms become complex when an aggregation uses multiple information sources, or when one aggregation is used by another aggregation. On the one hand, aggregation developers must respect the terms of resource owners and obtain their permission. On the other hand, they need to consider the impact of these terms on their own projects and whether they will bring some inconvenience or risks.

• Privacy and security: Some aggregation applications need to consider security and privacy, which can be obtained from the Web service provider (see Section 3. 5. Section 5) and implemented on the aggregation application side. For example, requiring users to log in, avoiding leaving cached content on the browser side, and using HTTP S.

Potential for exponential growth #

In recent years, the application of aggregation has become increasingly popular. Whether it is a small or large WebGIS application, the aggregation development model is basically competent. On the one hand, this is due to the increasingly abundant Web services and cloud GIS, and on the other hand, due to the popularity of browser-side programming interfaces in recent years, which have reduced the complexity of WebGIS development. Some netizens with a little knowledge of technology can do some simple aggregation applications by doing them, making the development of WebGIS applications popular.

Convergence also profoundly affects geographic information science and technology, including theories and methods of information sharing, geographic information mining and modeling methods, geospatial information interoperability, next-generation national basic spatial data facilities and cloud GIS and other fields. Convergence complements cloud computing and cloud GIS. With the support of the cloud, aggregation has a strong foundation and information source. aggregation can use cloud computing and cloud GIS, including other people’s facilities, platforms, data and services on the Internet (such as other people’s models), to complete its own work and projects, demonstrating the practical value of cloud computing and cloud GIS to people, winning social trust and investment for cloud GIS, and promoting the development of cloud GIS.

It should also be noted that the development of aggregation also faces some technical challenges and constraints from social issues. Web resources are unevenly distributed across regions. For example, many online maps and cloud GISs provide high-resolution images covering most parts of Europe and the United States, while only low-resolution images are provided for most rural areas on other continents. These places even lack a decent basic base map. There are also some countries and regions whose information privacy policies are too strict, restricting the sharing of information, or artificially adding errors in Web maps, which also limits the development of aggregation. There are a lot of valuable geographical information hidden in hundreds of millions of web pages on the Internet, but due to the lack of effective methods to parse it, most of these resources have not yet been developed.

Looking to the future, people’s concept of sharing will be further improved, and more high-quality Web resources will also emerge. Satellites in the air, many sensors on the ground and in rivers, lakes and seas are collecting a large amount of geographical data every day, which can be read and used quickly through the Web. With the popularization of mobile phones and mobile networks, the amount of spontaneous geographical information such as photos, videos and Weibo contributed by people is also exploding. The improvement of search engines and geographical information sharing portals will also make it easier for people to query and discover suitable Web resources. With the development of the Semantic Web, the search for Web resources will be more accurate, and aggregation can develop towards intelligence and automation. As these Web resources grow exponentially, the way they can be recombined will grow exponentially. Web users and GIS professionals will develop more creative and valuable WebGIS applications to meet a wide range of social needs.