Three-way handshaking - #TCP Is port available Open port (a
   door). 1) Hello 2) Hi I'm here. 1) Want to play 2) Okay! #howto
   #internet
   [vine id = "hY7purarJIF"]
   Three-way handshaking - #TCP Is port available Open port (a
   door). 1) Hello 2) Hi I'm here. 1) Want to play 2) Okay! #howto
   #internet