Both peers will start with a minimum MTU that is deemed to be safe (around 1200 bytes) and will independently start a path MTU discovery workflow from there. Th

Both peers will start with a minimum MTU that is deemed to be safe (around 1200 bytes) and will independently start a path MTU discovery workflow from there. That allows each side to increase the MTU without having a dependency on the other end. For path MTU discovery, peers can send PING frames in higher MTU datagrams and detect their loss (miss of their acknowledgement)