Certificate Authority Service (CAS) is a highly available, scalable Google Cloud service that enables you to simplify, automate, and customize the deployment, management, and security of private certificate authorities (CA). As it nears general availability, we want to provide guidance on how to deploy the service in real world scenarios. Today we’re releasing a whitepaper about CAS that explains exactly that. And if you want to learn more about how and why CAS was built, we have a paper on that too.
“How to deploy a secure and reliable public key infrastructure with Google Cloud Certificate Authority Service” (written by Mark Cooper of PKI Solutions and Anoosh Saboori of Google Cloud ) covers security and architectural recommendations for the use of the Google Cloud CAS by organizations, and describes critical concepts for securing and deploying a PKI based on CAS.
The purpose of a public key infrastructure (PKI) to issue certificates is largely dependent on the environment in which the PKI-issued certificates will be used. For common internet-facing services, such as a website or host where visitors to the site are largely unknown to the host, a certificate that is trusted by the visitor is required to ensure a seamless validation of the host. If a visitor’s browser hasn’t been configured to trust the PKI from which the certificate was issued, an error will occur. To facilitate this process, publicly trusted certificate authorities issue certificates that can be broadly trusted throughout the world. However, their structure, identity requirements, certificate restrictions, and certificate cost make them ineffective for certificate needs within an organizational or private ecosystem, such as the internet of things (IoT) or DevOps.
Organizations that have a need for internally trusted certificates and little to no need for externally trusted certificates can have more flexibility, control, and security in their certificates without a per-certificate charge from commercial providers.
A private PKI can be configured to issue the certificates an organization needs for a wide range of use cases, and can be configured to do so on a large scale, automated basis. Additionally, an organization can be assured that externally issued certificates cannot be used to access or connect to organizational resources.
The Google Cloud Certificate Authority Service (CAS) allows organizations to establish, secure and operate their own private PKI. Certificates issued by CAS will be trusted only by the devices and services an organization configures to trust the PKI.
Here are our favorite quotes from the paper:
“CAS enables organizations to flexibly expand, integrate or establish a PKI for their needs. CAS can be used to establish and operate as an organization’s entire PKI or can be used to act as one or more CA components in the PKI along with on-premises or other CAs.”
“There are several architectures that could be implemented to achieve goals within your organization and your PKI: Cloud root CA, cloud issuing CA and others”
“Providing a dispersed and highly available PKI for your organization can be greatly simplified through CAS Regionalization. When deploying your CA, you can easily specify the location of your CA.”
“CAS provides two operational service tiers for a CA – DevOps and Enterprise. These two tiers provide organizations with a balance of performance and security based on operational requirements.”