The TCP/IP / Process Status screen presents all of the active sockets.
A socket is the term for a TCP/IP communications connection. The states of connection displayed include Listen (waiting for a connection), Established (where communication is taking place) or Closing (where the communications connection is terminating).
Established TCP level sockets will have an LPort (local port) that is the same as the listening port but will have a randomly chosen FPort (foreign port). The combination of the local address, local port, foreign address and foreign port make a socket unique to the TCP/IP stack.
The Mini-Reports button brings up a pop-up screen that provides quick statistics for the count of local and foreign ports based on the address.
The column State has the following meaning when the Proto is TCP:
CLOSING
waiting for a terminate connection request acknowledgment from the remote site.
CLOSE-WAIT
waiting for a terminate connection request from the local user.
ESTAB
connection is open and the user can send and receive data. This is the normal state for data transfer.
FIN-WAIT-1
waiting for a terminate connection request from the remote TCP site or if waiting for acknowledgment of the terminate connection request that the process has sent previously.
FIN-WAIT-2
waiting for a termination of data to be received after having sent a FIN (termination of data being sent).
LISTEN
waiting for a connection request from any remote TCP site.
LAST-ACK
waiting for acknowledgment of the terminate connection request previously sent to the remote site (which includes an acknowledgment of its terminate connection request).
SYN-RCVD
waiting for an acknowledgment of a SYN-ACK sent in response to a SYN.
SYN-SENT
waiting for a SYN-ACK after having sent a SYN.
TIME-WAIT
waiting for sufficient time to pass (about two round trips) to be sure that stray packets are flushed from the network.