RFC 7234 - HTTP/1.1: Caching

Published: June 2014
Status: Standards Track
Authors: R. Fielding (Ed.), M. Nottingham (Ed.), J. Reschke (Ed.)

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Contents

• 1. Introduction
  • 1.1 Conformance and Error Handling
  • 1.2 Syntax Notation
    • 1.2.1 Delta Seconds
• 2. Overview of Cache Operation
• 3. Storing Responses in Caches
  • 3.1 Storing Incomplete Responses
  • 3.2 Storing Responses to Authenticated Requests
  • 3.3 Combining Partial Content
• 4. Constructing Responses from Caches
  • 4.1 Calculating Secondary Keys with Vary
  • 4.2 Freshness
    • 4.2.1 Calculating Freshness Lifetime
    • 4.2.2 Calculating Heuristic Freshness
    • 4.2.3 Calculating Age
    • 4.2.4 Serving Stale Responses
  • 4.3 Validation
    • 4.3.1 Sending a Validation Request
    • 4.3.2 Handling a Received Validation Request
    • 4.3.3 Handling a Validation Response
    • 4.3.4 Freshening Stored Responses upon Validation
    • 4.3.5 Freshening Responses via HEAD
  • 4.4 Invalidation
• 5. Header Field Definitions
  • 5.1 Age
  • 5.2 Cache-Control
    • 5.2.1 Request Cache-Control Directives
      • 5.2.1.1 max-age
      • 5.2.1.2 max-stale
      • 5.2.1.3 min-fresh
      • 5.2.1.4 no-cache
      • 5.2.1.5 no-store
      • 5.2.1.6 no-transform
      • 5.2.1.7 only-if-cached
    • 5.2.2 Response Cache-Control Directives
      • 5.2.2.1 must-revalidate
      • 5.2.2.2 no-cache
      • 5.2.2.3 no-store
      • 5.2.2.4 no-transform
      • 5.2.2.5 public
      • 5.2.2.6 private
      • 5.2.2.7 proxy-revalidate
      • 5.2.2.8 max-age
      • 5.2.2.9 s-maxage
    • 5.2.3 Cache Control Extensions
  • 5.3 Expires
  • 5.4 Pragma
  • 5.5 Warning
    • 5.5.1 Warning: 110 - "Response is Stale"
    • 5.5.2 Warning: 111 - "Revalidation Failed"
    • 5.5.3 Warning: 112 - "Disconnected Operation"
    • 5.5.4 Warning: 113 - "Heuristic Expiration"
    • 5.5.5 Warning: 199 - "Miscellaneous Warning"
    • 5.5.6 Warning: 214 - "Transformation Applied"
    • 5.5.7 Warning: 299 - "Miscellaneous Persistent Warning"
• 6. History Lists
• 7. IANA Considerations
  • 7.1 Cache Directive Registry
    • 7.1.1 Procedure
    • 7.1.2 Considerations for New Cache Control Directives
    • 7.1.3 Registrations
  • 7.2 Warn Code Registry
    • 7.2.1 Procedure
    • 7.2.2 Registrations
  • 7.3 Header Field Registration
• 8. Security Considerations
• 9. Acknowledgments
• 10. References
  • 10.1 Normative References
  • 10.2 Informative References
• Appendix A. Changes from RFC 2616
• Appendix B. Imported ABNF
• Appendix C. Collected ABNF

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About This Translation

This document is a production-grade translation following RFC translation standards. All ABNF syntax, technical field names, and protocol constants are preserved in English to ensure international standard precision.

Translation Completion Date: 2024
Translation Quality: Production-grade
Applicable Scenarios: HTTP cache implementation, CDN configuration, web performance optimization, technical documentation reference