Ory provides an open-source ecosystem of services that solve authentication and authorization. In this ecosystem, Ory Hydra and Ory Kratos play significant roles. Ory Hydra is an OAuth 2.0 and OpenID Connect provider. It is designed to handle authentication requests in high-scale and high-availability deployments. It issues access, refresh, and ID Tokens and is able to connect to any existing identity system. Ory Kratos, on the other hand, is an identity management server. It handles user registration, login, account recovery, and account verification. It can be used to build your own IAM system, and it's designed to be production-ready and easy to develop with. For example, in a self-hosted system, you might use Ory Hydra to handle OAuth 2.0 authentication requests from your application, while Ory Kratos could be used to manage user identities, including handling user registration and login. To scale these services, you can spin up another VM, Docker container, or pod of Ory Kratos or Ory Hydra with the same configuration. They can scale effortlessly to thousands of pods without any additional work. There is no need for complex key-value stores or message queues to serve high traffic environments. If you use multiple SQL instances, you can use HAProxy or similar technology for SQL load balancing. For more detailed information, you can refer to the [Ory Ecosystem Introduction](https://www.ory.sh/docs/ecosystem/projects) and [Ory Scalability Documentation](https://www.ory.sh/docs/self-hosted/operations/scalability).