TCP Connection States

ESTABLISHED

represents an open connection, data received can be delivered to the user, the normal state for the data transfer phase of the connection

CLOSED

represents no connection state at all

SYN-RECEIVED

represents waiting for a confirming connection request acknowledgment after having both received and sent a connection request

LISTEN

represents waiting for a connection request from any remote TCP and port

CLOSING

represents waiting for a connection termination request acknowledgment from the remote TCP

CLOSE-WAIT

represents waiting for a connection termination request from the local user

FIN-WAIT-2

represents waiting for a connection termination request from the remote TCP

FIN-WAIT-1

represents waiting for a connection termination request from the remote TCP, or an acknowledgment of the connection termination request previously sent

SYN-SENT

represents waiting for a matching connection request after having sent a connection request

LAST-ACK

represents waiting for an acknowledgment of the connection termination request previously sent to the remote TCP (which includes the acknowledgment of its connection termination request)

TIME-WAIT

represents waiting for enough time to pass to be sure the remote TCP received the acknowledgment of its connection termination request