ACM Digital Library Access Blocked by Cloudflare Security Check

The ACM Digital Library, a primary repository for computer science research papers and conference proceedings, is currently redirecting users to a Cloudflare security check. Visitors attempting to access dl.acm.org are presented with a message stating "Verifying you are human. This may take a few seconds." followed by a Cloudflare Ray ID and the note "Performance & security by Cloudflare."

This security measure is not an outage but a standard protective layer implemented by Cloudflare, a content delivery network and security service used by many academic and technical websites. The verification typically involves a brief challenge that may require clicking a checkbox or solving a simple puzzle to confirm the user is not an automated bot. The process usually completes within a few seconds, after which normal access to the ACM Digital Library is restored.

The ACM Digital Library hosts over 1.5 million technical articles, including papers from major conferences like SIGGRAPH, SIGCOMM, and ICML. Researchers, students, and industry professionals regularly rely on this resource for accessing cutting-edge work in computer science. When Cloudflare's security systems detect unusual traffic patterns, potential bot activity, or require additional verification from certain IP ranges, they implement these checks to protect the underlying servers from overload or malicious scraping.

For users experiencing prolonged verification delays or repeated challenges, common troubleshooting steps include:

• Clearing browser cache and cookies
• Disabling VPNs or proxy services that might trigger security flags
• Trying a different browser or device
• Ensuring JavaScript is enabled in browser settings

The Ray ID provided (9c2ef4b2e92fbf4c) serves as a unique identifier for this specific request, which can be useful if users need to contact ACM or Cloudflare support regarding persistent access issues. This security infrastructure helps maintain service availability for legitimate users while mitigating the impact of automated scraping tools that can degrade performance for human researchers.

Academic publishers increasingly rely on services like Cloudflare to manage the growing volume of automated traffic and protect their content from unauthorized mass downloading. While these security measures occasionally introduce friction for legitimate users, they represent a necessary trade-off to ensure sustained access to valuable research resources.