TCP Handshakes
Written by The Geekette on July 9, 2006 – 2:38 pmPosted in Networking |
To allow two hosts to communicate and exchange data reliably, TCP performs a three step handshake before any of the data is sent. This is when TCP guarantees that the data will arrive in tact by using a sequence and acknowledgement numbers. After all data is sent, TCP then performs a four step shutdown that concludes the session.
Three Step Startup
|
PC |
—————- SYN —————-> |
Server |
| <———— SYN ACK————– | ||
| —————- ACK —————-> |
Four Step Shutdown
|
PC |
—————FIN ACK ————-> |
Server |
| <—————ACK—————— | ||
| <———— FIN ACK————— | ||
| —————- ACK —————-> |
§


