In our previous posts about Verisign Informed™, we’ve talked about the importance of high-assurance infrastructure and how it is a critical underpinning for delivering at-time-of-use status information. We recounted some historical perspective on digital certificates that motivates the essential need to use evidence to build trust in internet security deployments, including revocation status which can change after the certificate is issued, and even after it expires. We then introduced an important idea – stale trust – and explained that failing to check for updated status, or relying on old data, results in stale (or absent) evidence, which is the essence of the stale trust problem. We will now discuss how, despite the importance of status to inform trust, browser makers have largely deprecated the Online Certificate Status Protocol (OCSP), one of the only tools available to determine certificate status on a per-certificate basis. While the reasoning behind that decision may be sound, we believe that the solution for certificate status in general lies in improving and modernizing the performance of OCSP, rather than abandoning it.
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