4.4 Connectionless RPCs With and Without a Delayed ACK
The following example illustrates the client sending an ACK packet.
Figure 25: Client sending an ACK packet
The corresponding delay between sequence 1 and sequence 2 is larger than 2 seconds, so 2 seconds after the last response PDU of call 1, the client sends an ACK packet whose sequence number is 1. This does not affect the PDUs for call sequence 2.