Google Cloud has enhanced its CDN and HTTP(S) Load Balancing services with the ability to support hybrid cloud customers. The new capability add support for external origins, enabling customers who have content, workloads or services that are on-prem or in other clouds to benefit of high availability, low latency, and convenience of a single anycast virtual IP address that HTTP(S) Load Balancing and Cloud CDN. This means Google CDN customers can pull content or reach web services that are on-prem or in another cloud, using Google’s global high-performance network.
The new hybrid configuration are the result of new internet network endpoint groups, which allow the customer to configure a publicly addressable endpoint that resides outside of Google Cloud, such as a web server or load balancer running on-prem, or object storage at a third-party cloud provider. From there, the customer can serve static web and video content via Cloud CDN, or serve front-end shopping cart or API traffic via an external HTTP(S) Load Balancer, similar to configuring backends hosted directly within Google Cloud.
https://cloud.google.com/blog/products/networking/enabling-hybrid-deployments-with-cloud-cdn-and-load-balancing