A Personalized History of Computer Communications 1950s -1970s and Beyond

1. A Personalized History of Computer Communications1950s -1970s and Beyond Mischa Schwartz Charles Batchelor Professor Emeritus of Electrical Engineering Columbia University New York, NY 10027

2. 1950s, 1960s • US Defense Activity- SAGE Network, 1950s, Radar Data NIKE Zeus Data Network, AT&T Bell Labs, circa 1960 Paul Baran, Rand Corp., early 1960s, Survivable Data Networks • Commercial Data Networking: Airlines, Banks, … • Computer Time sharing Project Mac, MIT (GE Corp.), early 1960s

3. Commercial Data Networking, 1950s, 1960s • Airline Reservation Systems American Airlines, LGA, 1952 American Airlines/IBM Sabre, 1959 IBM PARS, 1961 SITA, 1964 • Banking Networks Ex: Lloyds Bank, UK, 1966 (IBM)

4. Airline Reservation Systems • PARS, 1961 on • SITA, 1964 on

6. Original PARS System

10. SITA Network

12. Banking Networks

14. Late 1960s to mid-1970s • Private Data Networks- Tymnet, GE Information Services Network • Proprietary Computer Communication Architectures (Computer Manufacturers) Ex: IBM SNA • ARPA, ARPAnet

15. Private Data Networks, late 1960s-1970s • Time-shared capability • Terminal-oriented • Data processing: Interactive, Batch processing Ex: GE Information Services Network TYMNET (Tymshare, Inc.) later- Networking functions

16. GE Information Services Network Centralized Hosts

20. TYMNET Distributed Hosts Virtual Routing

23. Computer Manufacturers, late 1960s on •Teleprocessing Networks- Specialized Communication Controllers • Proprietary Communication Architectures Ex: IBM SNA (later DNA, BNA,…) Specialized hardware, software Layered architecture

25. IBM SNA System Network Architecture: Layered Architecture

29. ARPA, ARPAnet:Formative Years • 1962, MIT: J.C.R. Licklider, “Globally interconnected computers” Len Kleinrock, doctoral dissertation (1964, “Communication Nets: stochastic message flow and delay”, McGraw-Hill) •1965, Larry Roberts, MIT Lincoln Lab, interconnected-computer expt. Donald Davies, British NPL, “packet” message vs. packet switching

30. ARPA, ARPAnet: Network Concept/Development • 1967, Roberts, ARPA: “computer utility concept” BBN contract, IMPs • 1969, 4-node ARPAnet, datagram routing (1970, Host-to-Host protocol, NCP) Measurements- “incestuous” traffic! • 1974, Robert Kahn and Vint Cerf- TCP (1978-TCP/IP) 24 node-ARPAnet • 1976, 56 nodes

34. International Standardization Efforts • Early 1970s, CCITT, public data networking • 1976, X.25 Datapac (Canada), first public data network • 1978-1980, ISO, OSI Reference Model: 7-layer communications architecture

35. X.25 Network-Interface Recommendation

37. OSI Reference Model Seven-Layer Architecture

40. ARPAnet → Internet • 1980-1983, TCP/IP adopted; replaces NCP • 1985, 1986, NSFNET organized, regional nets encouraged: Ex: NYSERNET • 1986-1995 NSFNET expands, commercial service • 1995 on: full-fledged Internet!

41. Internet and Beyond • Millions of Hosts! • Multimedia traffic • Wireless connectivity: 3G cellular data, 4G all packet-switched all-purpose cellphones 802.11 connections… • Future? Your guess is as good as mine! But see following:

42. Focus on Personal Networks? Example: (with due respect to Magda!) MAGNET (European vision) “My Personal Adaptive Global NET”