TheIntegration Runtime (IR)is the compute infrastructure used by Azure Data Factory to provide data integration capabilities across different network environments. If you need to perform data integration and orchestration securely in a private network environment, which does not have a direct line-of-sight from the public cloud environment, you can install a self-hosted IR on premises behind your corporate firewall, or inside a virtual private network.
Untill now, you were required to create at least one such compute infrastructure in every Data Factory by design for hybrid and on-premise data integration capabilities. Which implies if you have ten such data factories being used by different project teams to access on-premise data stores and orchestrate inside VNet, you would have to create ten self-hosted IR infrastructures, adding additional cost and management concerns to the IT teams. With the new capability of self-hosted IR sharing, you can share the same self-hosted IR infrastructure across data factories.