For ordinary TCP packets, which of the following flag-bit combinations can occur?
A SYN+ACK segment is the standard server response during the TCP three-way handshake. A FIN may coexist with URG because FIN indicates that the sender has no more data to send, while URG independently makes the urgent-pointer field significant. RST is used to reset a connection and is not normally combined with SYN or FIN. RFC 9293 defines these flag meanings and specifies SYN,ACK segments for connection establishment.
Community Discussion