ok, that is what i am progresively understanding.
I also found that "the links" system that runned in japan between 1986 and 1994. providing network extension to games like laydock2.
It was like the "minitel" we could find in france.

I dont know how exactly worked "the links" but better i write "the links" providing connection, not network, network is diferent servers & clients all conected together, i think "the links" connect you some servers (news, games, etc) but this is not a network.