How do you optimize the performance and availability of PKI revocation servers?

1 Choose the right revocation method

There are different methods to check the revocation status of a certificate, such as certificate revocation lists (CRLs), online certificate status protocol (OCSP), and OCSP stapling. Each method has its own advantages and disadvantages in terms of scalability, security, and latency. For example, CRLs are easy to implement and cache, but they can be large and outdated. OCSP is more responsive and accurate, but it requires more network and server resources. OCSP stapling is a variation of OCSP that reduces the load on the revocation server by allowing the certificate holder to attach a signed OCSP response to the certificate. You should choose the revocation method that best suits your needs and environment.

2 Implement caching and load balancing

Caching and load balancing are two techniques that can improve the performance and availability of PKI revocation servers. Caching allows the revocation server to store frequently requested or recently updated revocation data in memory or disk, reducing the need to access the database or generate new responses. Load balancing distributes the incoming requests among multiple revocation servers, preventing overload and ensuring redundancy. You can use hardware or software solutions to implement caching and load balancing, depending on your budget and configuration.

3 Monitor and troubleshoot revocation issues

Monitoring and troubleshooting revocation issues are essential to ensure the reliability and security of PKI revocation servers. You should use tools and metrics to track the status, performance, and errors of your revocation servers, such as response time, throughput, availability, and logs. You should also test your revocation servers regularly to verify their functionality and compliance with standards and policies. If you encounter any revocation issues, such as expired certificates, invalid responses, or network failures, you should identify the root cause and resolve them as soon as possible.

5 Optimize revocation policies and settings

Optimizing revocation policies and settings can help you reduce the complexity and overhead of PKI revocation servers. You should review your revocation policies and settings periodically and adjust them according to your needs and requirements. For example, you can define the frequency, validity, and size of your CRLs, the timeout and retry intervals of your OCSP requests, and the frequency and duration of your OCSP stapling. You can also use certificate extensions, such as CRL distribution points (CDPs) and authority information access (AIA), to specify the location and method of revocation checking for each certificate.

6 Educate and inform your users and stakeholders

Educating and informing your users and stakeholders are crucial to ensure the effectiveness and usability of PKI revocation servers. You should communicate clearly and transparently about your revocation policies and procedures, such as the reasons, methods, and impacts of revoking a certificate. You should also provide guidance and support to your users and stakeholders on how to check the revocation status of a certificate, how to report a compromised or lost certificate, and how to resolve any revocation issues. Educating and informing your users and stakeholders can help you foster trust and compliance with your PKI system.