how old is the enternet?
>The ARPAnet, the predecessor of the Internet, was born in November 1969, making the Internet 50 years old. In January 1983, ARPAnet shifted to the TCP/IP protocol, which to this date powers the modern Internet.
The core backbone of the modern internet began as the National Science Foundation Network (NSF Net) in 1985. It ran as a government non-profit network that was intended to link together several academic and military networks that had existed prior.
These predecessor networks were things like ARPANET, and various university networks that at one time carried things like UUCP (the protocol that carried USENET), and research institutes, etc.
In the 70s, when these networks developed, commercial time sharing networks also developed. These were things like CompuServ, and AOL's predecessor orgs which provided timesharing (basically, back in these days, if your business couldn't afford a big-ass PDP-11, you'd rent processor time from a timesharing provider and be billed by how much proc time your applications took to run), email services, and similar shit like this.
Anyway, NSF Net began by linking together the research, university and military networks through the 80s. Note that when I said "research institutes", this included commercial research, e.g. like Bell, CompuServ, etc, had research connections to the network, but couldn't commercialize the network's use. In this same period, networks that would eventually tie into NSF Net such as the Computer Science Network linked with some academic systems in France, Japan, etc, and this extended the internet internationally.
In 1991, NSF Net's ToS changed to allow commercial use, and so timesharing companies like CompuServ and AOL took advantage of this to become some of the first commercial ISPs.
From 1991 to 1995, the commercial local networks ended up forming independent links between themselves, making the original government-funded NSF Net redundant. Accordingly, NSF Net's infrastructure was decommissioned in 1995 to be replaced by the commercial infrastructure that made up the new internet backbone.
This commercial backbone is ultimately the core of the modern internet.
So, the earliest constituent predecessor networks go back to like ARPANET in the late 60s, with most of these forming in the 70s. They all got linked together between 1985 and 1995 through the government funded NSF Net, and then the modern commercial backbone formed and finally took over between 1991-1995, with the modern internet ultimately being the continuation of the status quo from 1995.