What Happened to IBM Networking? How Cisco Destroyed a $9 Billion Empire

IBM’s SNA network was a nine-billion-dollar-a-year empire that controlled enterprise computing more completely than any single company controls any technology market today. Then it was dissolved in a single press announcement, its patents sold to Cisco, its engineers reassigned. The story most people know says TCP/IP won because open standards beat proprietary ones. The actual sequence is more specific: a US Department of Defense mandate in March 1982 established TCP/IP’s institutional installed base before the commercial networking market had formed; the National Science Foundation compounded it with the NSFNET backbone from 1986; and in 1993, IBM’s own engineers published the RFC that gave every IBM customer a migration path off IBM’s own hardware. This is the forensic account of how the internet’s architecture was decided, and what it cost the company that built the network the world ran on.