I recommend reading Data Communications - The First 2500 Years G.J. Holzmann Proc. IFIP World Computer Congress, Hamburg Germany, August 1994, (Invited pa

I recommend reading Data Communications - The First 2500 Years G.J. Holzmann Proc. IFIP World Computer Congress, Hamburg Germany, August 1994, (Invited paper). http://spinroot.com/gerard/pdf/hamburg94b.pdf http://spinroot.com/gerard/pdf/hamburg94b.pdf The book: The Early History of Data Networks G.J. Holzmann and B. Pehrson IEEE Computer Society Press, Los Alamitos CA, (John Wiley & Sons), October 1994. The basic ideas of relaying, encoding, separation of control/data information, error control, flow and rate control go back surprisingly far.