Thanks! So we can see these ACKs as "wait and synchronize" signals I suppose? However how can we ensure an "all or nothing" between all parties trying to ACK a

Thanks! So we can see these ACKs as "wait and synchronize" signals I suppose? However how can we ensure an "all or nothing" between all parties trying to ACK a conditions they're mutually dependent on? I.e. transactionality or atomicity?