The 1st generation of registries were purely a paper-based list maintained in registers. As part of early computerisation, such lists got digitised giving birth to the 2nd generation of registries. They were digitised data, but typically maintained in an internal database.
With the advent of the Internet and smartphones, as more systems went online, data also migrated to 3rd generation portal based systems. They partially addressed liveness and reuse. But such portals can only be used by humans by visiting a portal or mobile app, making it non-scalable and costly by not allowing other systems to access data in an automated and trustworthy manner.
4th generation electronic registries solve the three core issues with portal based approach by having open APIs through which digitally signed data is made available for read, search, and subsequent usage. Open APIs allow automated access by external systems, making data use scalable and cost efficient. Digitally signed data available via these APIs brings in tamper-resistance, electronic verifiability, and portability of data. Such registries should be designed to allow viewing and updating of data (with appropriate verification workflow) by the person or entity whose data it is by aligning incentives.
By creating 4th generation electronic registries that allow data to be kept up to date, offering open APIs for consented access, and providing data in digitally signed fashion, India can dramatically reduce the cost of repeated data collection and maintenance of various master data. Examples of registries include geographical data registry, institution registry, school registry, teacher registry, and so on.