Google Compute Engine ("GCE") uses Persistent Disk Asynchronous Replication ("PDAR") for cross-region replication with RPO < 1 minute.
(Learn more about PDAR: https://cloud.google.com/compute/docs/disks/async-pd/about.)

PDAR replicates data belonging to independent VMs or groups of dependent VMs with Consistency Groups ("CG"). JetStream for GCE Disaster Recovery Orchestration automates PDAR configuration, minimizing the effort required to manage DR and greatly speeding the overall process.

JSDRO is an independent software solution that can be acquired from the GCP Marketplace with metering and billing managed through the Marketplace. Once subscribed, Asynchronous Replication Orchestration ("ARO") software (the orchestration appliance and its deployment scripts) is downloaded from the JetStream portal. ARO is implemented in the form of an Asynchronous Replication Orchestration Virtual Appliance ("AROVA") running on “top” of PDAR.

Also see:

View: Introduction

View: Definitions, Acronyms and Abbreviations

View: Persistent Disk Storage Scopes and ARO

View: AROVA Introduction