(D)TLS 1.3 support for 0.5-RTT (round trip time) data has been introduced to wolfSSL in the latest release (5.6.6). 0.5-RTT data is an optimization in (D)TLS 1.3 that significantly reduces latency and improves overall performance of application data. The full handshake requires two full round trips to start sending data while this functionality allows the server to send application data along with its final flight of handshake messages. This new addition works well with our support for early data (also known as 0-RTT data). An embedded device is able to resume a connection, send early data with its connection request, and receive a response immediately within one RTT.
Client Server
ClientHello -------->
ServerHello
EncryptedExtensions
CertificateRequest
Certificate
CertificateVerify
Finished
<-------- 0.5-RTT Application Data
Certificate
CertificateVerify
Finished -------->
Application Data <-------> Application Data
Diagram showing 0.5-RTT data in a full TLS 1.3 handshake
If you would like to learn more about (D)TLS 1.3 in wolfSSL, please contact us at facts@wolfSSL.com or call us at +1 425 245 8247.
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