An acknowledgment, commonly abbreviated as ACK, is a fundamental mechanism in reliable communication protocols like TCP. When a receiving node successfully processes a transmitted frame or packet, it returns an ACK to the sender. If the sender does not receive this confirmation within a specified timeout period, it assumes the data was lost or corrupted and retransmits the payload.
The client is sending the SYN, but it's never getting the acknowledgment back from the server, so the handshake fails.
Also heard as
- ACK
Related terms
TCP/IP
Transmission Control Protocol/Internet Protocol is the foundational suite of communication protocols used to interconnect network devices.
Latency
The time it takes for a packet of data to travel from its source to its destination.
Jitter
The variation in the delay of received packets or the deviation of a digital signal from its precise timing.