SSH certificate-based authentication offers a scalable and secure alternative to traditional SSH public key authentication, which can become complex and unwieldy with large teams and infrastructure. This approach introduces a centralized trust model where designated certificate authorities sign user and host public keys to produce short-lived certificates vouching for their identity. SSH certificates come with built-in expiration, identity information, and can be revoked or reissued at any time, making them more flexible and secure than long-lived SSH keys. Implementing SSH certificate-based authentication requires upfront engineering effort, but it provides a centralized control plane, auditable access control, and short-lived credentials that simplify the operational complexity of managing SSH access. Solutions like Infisical SSH can abstract away this complexity, allowing teams to focus on registering users and hosts and specifying who should have access to what. As companies like Meta, Uber, and Google already adopt this model, it's likely that more teams will follow suit in the future.