AWS Certificate Manager

AWS Certificate Manager (ACM) addresses the complex and time-consuming process of managing SSL/TLS certificates, a critical aspect of securing web applications and internal resources. The core challenge it tackles is the manual handling of certificate issuance, renewal, and deployment, which can lead to downtime and security vulnerabilities if not managed properly.

ACM's technical architecture revolves around integrating with various AWS services to automate the certificate lifecycle. It allows you to request, manage, and deploy public and private SSL/TLS certificates. For public certificates, ACM handles the validation process, including domain validation via DNS or email, and issues certificates that are trusted by most browsers and devices. Private certificates, on the other hand, can be issued by a private Certificate Authority (CA) managed through AWS Private CA, which is particularly useful for securing internal resources.

Operationally, ACM simplifies the process by automating certificate renewals, eliminating the need for manual intervention. However, it requires careful configuration, such as setting up CAA records to ensure only authorized CAs can issue certificates for your domains. Additionally, certificates signed by a private CA must be installed in client trust stores, as they are not trusted by default.

From a technical standpoint, ACM supports various validation methods, including DNS and email validation, and integrates with AWS services like Elastic Load Balancer and Amazon CloudFront. The API allows for programmatic management using AWS SDKs and command-line tools, with requests signed using Signature Version 4 for security. When using CloudFormation, you can declare ACM certificate resources with specific properties such as domain names, validation methods, and key algorithms.

In terms of limitations, public ACM certificates cannot be installed on all Amazon EC2 instances, specifically those not connected to a Nitro Enclave. Moreover, the management of private certificates requires additional steps to ensure trust in client environments. Despite these considerations, ACM significantly reduces the operational overhead associated with certificate management, ensuring continuous security and uptime for your applications.