Ssenkahdavic on 09 January 2014
I would bet some marketing person took a Cisco networking class, saw the depiction of the Internet as a "cloud" and started the buzz. I have a 20 year old lab guide that has it depicted as such.
He'll I have an old IBM token ring book from the 80s that uses a cloud for the lan. It's a symbol to mean networking in the place of a full topology diagram.
