TCP States
Authorsupport support Article Reference NumberAA-05001 Views1893 0 Rating/ Voters

TCP States

An explanation of common TCP states.


SYN_SEND Indicates active open.

SYN_RECEIVED Server just received SYN from the client.

ESTABLISHED Client received server's SYN and session is established.

LISTEN Server is ready to accept connection.

NOTE: See documentation for listen() socket call. TCP sockets in listening state are not shown - this is a limitation of NETSTAT. For additional information, please see the following article in the Microsoft Knowledge Base:

134404 NETSTAT.EXE Does Not Show TCP Listen Sockets

FIN_WAIT_1 Indicates active close.

TIMED_WAIT Client enters this state after active close.

CLOSE_WAIT Indicates passive close. Server just received first FIN from a client.

FIN_WAIT_2 Client just received acknowledgment of its first FIN from the server.

LAST_ACK Server is in this state when it sends its own FIN.

CLOSED Server received ACK from client and connection is closed.

Comments(0)
There are no comments for this article.
Info Add Comment
Nickname: Email (will not be shown): Subject: Comment:
Quick Jump Menu
Subscribe to updates Subscribe to Updates
Email to a frien Email to a Friend
Print Print Article
Info Vote
Info Ask a Question
Email (will not be shown): Subject: Question: