Linux process status

The connection process is represented by a series of States, which are:listen,syn-sent,syn-received,established,fin-wait-1,fin-wait-2,close-wait,closing,last-ack,time-wait and CLOSED. the meanings of each state are as followsclosed indicates no connection:LISTEN-listens for connection requests from remote TCP ports;syn-sent-waits for a matching connection request after the connection request is sent;syn-received-Waits for confirmation of the connection request after receiving and sending a connection request;established-represents an open connection where data can be transmitted to the user;fin-wait-1-A connection interruption request waiting for a remote TCP, or confirmation of a previous connection interruption request;fin-wait-2-Waits for a connection interrupt request from a remote TCP;close-wait-waits for a connection interruption request from a local user;CLOSING-Wait for the remote TCP acknowledgement of the connection interruption;Last-ack-Acknowledgement of the connection interrupt request that was originally sent to the remote TCP;time-wait-Wait enough time to ensure that the remote TCP receives the acknowledgement of the connection interrupt request;CLOSED-no connection status;The TCP connection process is the transition of the state, prompting the user invocation of the state transition: Open,send,receive,close,abort and status; The data segments that are transmitted, particularly those that include the following tagged data segments Syn,ack,rst and fin There is a timeout, and the TCP state changes when the above is said to be the case.

SYN is the abbreviation for English synchronize (sync)! Sync the signal! is the C/s under the TCP three handshake, the first time the client sends a connection signal, then receives the server's ACK signal, namely confirms (acknowledgement) the signal.

ack  English abbreviation: ACK (acknowledge Character)  
Chinese translation: confirmation character  

explanation: in the data communication transmission, A Transmission control character that is sent to the receiving station. It indicates that the data sent has been accepted without error.  
ACK: 
Usually the ACK signal has its own fixed format, the length size, which is returned by the receiving party to the sender. The format depends on the network protocol being taken. When the sender receives an ACK signal, it can send the next data. If the sender does not receive a signal, the sender may resend the current packet, or it may stop transmitting the data. Depending on the network protocol used. An ACK signal is usually an ASCII character, and the ACK signal differs in different protocols.  
Open classification:  
communication

RST: Abbreviation: Reset Reconnect bit ~ Notify re-establish TCP connection when rst=1

FIN: It's supposed to be finall.

Linux process status