By using a network protocol analyzer such as Wireshark, a Network Administrator can determine if congestion is present on their network. The key is looking for duplicate ACKs. Consistent duplicate ACKs are an indication that network congestion may be present. The problem is worth investigating. To manage the reliability of data between two endpoints, TCP uses ordered sequence numbers (SYN) and acknowledgements (ACKs). For example, data is broken up into packets, and each packet is given a sequence number. (Data to be sent) = Packet A – SYN 1 , Packet B – SYN2 , Packet C – SYN3 Each packet is sent in sequential order, and as each packet arrives to its destination, the destination endpoint sends a unique acknowledgement (ACK) back to the transmitter as a way to verify the data has been received in its proper order. ACK 1 [Packet A – SYN1], ACK 2 ACK 1 [Packet B – SYN2], ACK 3 [Packet A – SYN3], If the data arrives out of order, a duplicate ACK is ...