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Appendix D. Backward Compatibility

This appendix describes backward compatibility considerations for TLS 1.3.

D.1. Negotiating with an Older Server

How TLS 1.3 clients negotiate with TLS 1.2 servers.

D.2. Negotiating with an Older Client

How TLS 1.3 servers handle TLS 1.2 clients.

D.3. 0-RTT Backward Compatibility

Considerations for 0-RTT with older protocol versions.

D.4. Middlebox Compatibility Mode

How TLS 1.3 maintains compatibility with legacy middleboxes.

Security considerations when supporting older TLS versions.


Complete Compatibility Guidance: For complete backward compatibility specifications and recommendations, please refer to Appendix D of RFC 8446.

中文完整版本: 完整的向后兼容性说明请参见中文翻译版本。