I am implementing WebRTC stack from scratch as a hobby project.I cannot understand when does the DTLS negotiation is supposed to start ? BEFORE or AFTER the candidate nomination is completed with triggered check ?

when I connected two chrome client in p2p and monitored the traffic on Wireshark it seems that the DTLS client hello is sent before the candidate has been nominated , What I don’t understand is why its establishing the dtls before even knowing the actual nominated candidate pair.