“…In the first step, the Initiator computes xP (i.e., P, as a point on E, added to itself x times using the addition law on E); encrypts xP, the IDi, and the IDr using the Responder's public key (e.g., K_PUBr=H1(IDr||date)); and includes this encrypted information in MESSAGE_1 sent to the Responder. In this step, encryption refers to IBE as described in [RFC5091] and [RFC5408].…”