Hello all, I’m working on the MESI_Two_Level protocol and I’ve noticed there is a double ACK process between Memory and L2 For example: L2 receives a MEM_INV L2 deals with it and sends back a clean ACK and goes into the intermediate state Memory receives it Memory sends an ACK to the L2 I was hoping to understand this design decision, as I am having trouble understanding why it is necessary for the double ACK, and the L2 not immediately going into NP upon sending back its ACK. Best, Arteen