What is essential difference between message switching and packet switching?
message switching: sends the entire message to an alt router route to get to the end user. packet switching: breaks the message into packets and sends them to the end user, using the path with the lightest load or least traffic at the time of transmit. Packets can be sent in order or not and are re-assembled at the recieving end in the correct order by packet number. This is a very general discription of the formats. Go to Cisco.com for more details.