The first management team consisted of Landweber (University of Wisconsin), Farber (University of Delaware), Peter J. Denning (Purdue University), Anthony C. Hearn (RAND Corporation), and Bill Kern from the NSF. Once CSNET was fully operational, the systems and ongoing network operations were transferred to BBN Technologies (BBN) of Cambridge, Massachusetts by 1984.
The Purdue team, consisting of Peter Denning, Douglas Comer, and Paul McNabb, was responsible for designing and building the kernel interfaces that would allow sites outside of the ARPANET infrastructure to connect via public X.25 networks, such as Telenet. The mechanism allowed systems with TCP/IP network stacks to use an X.25 network device, with IP datagrams being sent through dynamically allocated X.25 sessions. Purdue and other sites with ARPANET access would act as gateways into the ARPANET, allowing non-ARPANet sites to have email, telnet, ftp, and other forms of network access directly into the ARPANET.
By 1981, three sites were connected: University of Delaware, Princeton University, and Purdue University. By 1982, 24 sites were connected expanding to 84 sites by 1984, including one in Israel. Soon thereafter, connections were established to computer science departments in Australia, Canada, France, Germany, Korea, and Japan. CSNET eventually connected more than 180 institutions. CSNET History
One of the earliest experiments in free software distribution on a network, netlib, was available on CSNET.
CSNET was a forerunner of the National Science Foundation Network (NSFNet) which eventually became a backbone of the Internet. CSNET operated autonomously until 1989, when it merged with Bitnet to form the Corporation for Research and Educational Networking (CREN). By 1991, the success of the NSFNET and NSF-sponsored regional networks had rendered the CSNET services redundant, and the CSNET network was shut down in October 1991.ftp://athos.rutgers.edu/resource-guide/chapter6/section6-6.txt
The email relaying service was called Phonenet, after the telephone-specific channel of the MMDF software developed by Crocker. The CSNET name service allowed manual and automated email address lookup based on various user attributes, such as name, title, or institution. The X.25 tunneling allowed an institution to connect directly to the ARPANET via a commercial X.25 service (Telenet), by which the institution's TCP/IP traffic would be tunneled to a CSNET computer that acted as a relay between the ARPANET and the commercial X.25 networks. CSNET also developed dialup-on-demand (Dialup IP) software to automatically initiate or disconnect SLIP sessions as needed to remote locations. CSNET was developed on Digital Equipment Corporation (DEC) VAX-11 systems using BSD Unix, but it grew to support a variety of hardware and operating system platforms.