I used to call a chat BBS - a single BBS with multiple modems that allowed you to see who was online and send messages to other users.

The sysops could even use one modem to dial into a 2nd chat BBS, and users of both systems could chat with each other. The 2nd BBS could dial into a 3rd, and so on. We'd participate in nation-wide chats about once a month. Definitely sounds networked to me.