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IP Addresses in Certificates
We are planning to add support for validating and including IP addresses in certificates.
ECDSA Root and Intermediates
Currently Let’s Encrypt only signs end-entity certificates with RSA intermediates. We now have an ECDSA root and intermediates, but still need to submit them to root programs and integrate them into our issuance system.
Completed Features
Multi-Perspective Validation
- Enabled: February 19, 2020
We now validate domain control from multiple network perspectives.
Certificate Transparency Log
- Enabled: May 15, 2019
We now operate a Certificate Transparency log.
TLS ALPN Challenge Support
- Enabled: July 12, 2018
We’ve specified and implemented a replacement for the TLS-SNI validation method, which was discontinued for security reasons. Introducing a replacement was important for subscribers who only want to use port 443 for validation.
Embed SCT receipts in certificates
- Enabled: March 29, 2018
Wildcard Certificates
- Enabled: March 13, 2018
ACME v2 API
- Enabled: March 13, 2018
IDN Support
- Enabled: October 20, 2016
Let’s Encrypt now supports issuance for Internationalized Domain Names (IDNs).
Full IPv6 Support
- Enabled: July 26, 2016
Initially, only parts of the Let’s Encrypt API infrastructure could communicate via IPv6. This prevented IPv6-only systems from being able to fully interact with Let’s Encrypt. This has been resolved - IPv6 support has been enabled for all functionality.
Windows XP Certificate Compatibility
- Enabled: March 25, 2016
Resolved an issue with our certificate chain that prevented Let’s Encrypt certificates from being accepted by browsers on Windows XP.
ECDSA Signing Support
- Enabled: February 10, 2016
Added the ability for Let’s Encrypt to sign ECDSA keys with Let’s Encrypt’s RSA intermediates. Support for signing ECDSA keys with a full ECDSA cert chain will be added later.
ACME DNS Challenge Support
- Enabled: January 20, 2016
Let’s Encrypt allows validation via DNS records as defined in the ACME specification.