DTLS 1.3 can be found here: https://tools.ietf.org/html/draft-ietf-tls-dtls13-38
Thank you.
The HRR is used in DTLS 1.3 for DDoS prevention.
This makes sense since DTLS is over UDP, but TLS is over TCP, so it's already undergone the SYN/ACK handshake to establish there's an actual peer with a reachable address. I'm thinking that the majority of the time, connections are going to be legitimate, so optimize for that case. Keep the first ClientHello in memory, send a simple unpredictable cookie (maybe 128 bits ?) and just check that it gets echoed. Then do all the validation of the second ClientHello against the first one that you have to do anyway. Monitor the activity occurring and if the server decides it's being attacked in some way, maybe then switch to stateless HRR (if this makes sense) or do whatever other countermeasures are appropriate. Mike _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
