Thirty institutions are connected to the ARPANET

1973

ARPANET Map, 1973 Bob Kahn Vint Cerf

Thirty institutions are connected to the ARPANET. The network users range from industrial installations and consulting firms like BBN, Xerox PARC and the MITRE Corporation, to government sites like NASA’s Ames Research Laboratories, the National Bureau of Standards, and Air Force research facilities.The ICCC demonstrations prove packet-switching a viable technology, and ARPA (now DARPA, where the ‘D’ stands for ‘Defense’) looks for ways to extend its reach. Two new programs begin: Packet Radio sites are modeled on the ALOHA experiment at the University of Hawaii designed by Norm Abramson, connecting seven computers on four islands; and a satellite connection enables linking to two foreign sites in Norway and the UK. Bob Kahn moves from BBN to DARPA to work for Larry Roberts, and his first self-assigned task is the interconnection of the ARPANET with other networks. He enlists Vint Cerf, who has been teaching at Stanford. The problem is that ARPANET, radio-based PRnet, and SATNET all have different interfaces, packet sizes, labeling, conventions and transmission rates. Linking them together is very difficult. Kahn and Cerf set about designing a net-to-net connection protocol. Cerf leads the newly formed International Network Working Group. In September 1973, the two give their first paper on the new Transmission Control Protocol (TCP) at an INWG meeting at the University of Sussex in England. Meanwhile, at Xerox PARC, Bob Metcalfe is working on a wire-based system modeled on ALOHA protocols for Local Area Networks (LANs). It will become Ethernet.

 

The ARPANET grows by ten more nodes in the first 10 months of 1972

1972

Steve Wozniak's 'Blue Box' People get on my nerves I am not sure I understand you You should pay more attention Suppose you should pay more attention You're entitled to your opinion What makes you think I am entitled to my own opinion? -- from a conversation between PARRY and the ‘Doctor’ via the ARPANET

The ARPANET grows by ten more nodes in the first 10 months of 1972. The year is spent finishing, testing and releasing all the network protocols, and developing network demonstrations for the ICCC.At BBN, Ray Tomlinson writes a program to enable electronic mail to be sent over the ARPANET. It is Tomlinson who develops the ‘user@host’ convention, choosing the @ sign arbitrarily from the non-alphabetic symbols on the keyboard. Unbeknownst to him, @ is already in use as an escape character, prompt, or command indicator on many other systems. Other networks will choose other conventions, inaugurating a long period known as the e-mail ‘header wars.’ Not until the late 1980s will ‘@’ finally become a worldwide standard. Following the lead of Intel’s 4004 chip, hand-held calculators ranging from the simple Texas Instruments four-function adding machines to the elaborate Hewlett-Packard scientific calculators immediately consign ordinary slide rules to oblivion. Xerox PARC develops a program called Smalltalk, and Bell Labs develops a language called ‘C.’ Steve Wozniak begins his career by building one of the best-known ‘blue boxes;’ tone generators that enable long-distance dialing while bypassing the phone company’s billing equipment. The ICCC demonstrations are a tremendous success. One of the best known demos features a conversation between ELIZA, Joseph Weizenbaum’s artificially-intelligent psychiatrist located at MIT, and PARRY, a paranoid computer developed by Kenneth Colby at Stanford. Other demos feature interactive chess games, geography quizzes, and an elaborate air traffic control simulation. An AT&T delegation visits ICCC but leaves in puzzlement.

 

he ARPANET begins the year with 14 nodes in operation

1971

ARPANET map, 1971 BBN's TIP Advertisement for the Intel 4004

The ARPANET begins the year with 14 nodes in operation. BBN modifies and streamlines the IMP design so it can be moved to a less cumbersome platform than the DDP-516. BBN also develops a new platform, called a Terminal Interface Processor (TIP) which is capable of supporting input from multiple hosts or terminals.The Network Working Group completes the Telnet protocol and makes progress on the file transfer protocol (FTP) standard. At the end of the year, the ARPANET contains 19 nodes as planned. Intel’s release of the 4004, the first ‘computer on a chip,’ ushers in the epoch of the microprocessor. The combination of memory and processor on a single chip reduces size and cost, and increases speed, continuing the evolution from vacuum tube to transistor to integrated circuit. Many small projects are carried out across the new network, including the demonstration of an aircraft-carrier landing simulator. However, the overall traffic is far lighter than the network’s capacity. Something needs to stimulate the kind of collaborative and interactive atmosphere consistent with the original vision. Larry Roberts and Bob Kahn decide that it is time for a public demonstration of the ARPANET. They choose to hold this demonstration at the International Conference on Computer Communication (ICCC) to be held in Washington, DC, in October 1972.

 

Nodes are added to the ARPANET at the rate of one per month

970

DEC's PDP-10 DEC's PDP-11

Nodes are added to the ARPANET at the rate of one per month.Programmers Dennis Ritchie and Kenneth Thompson at Bell Labs complete the UNIX operating system on a spare DEC minicomputer. UNIX combines many of the time-sharing and file-management features offered by Multics and wins a wide following, particularly among scientists. Bob Metcalfe builds a high-speed (100 Kbps) network interface between the MIT IMP and a PDP-6 to the ARPANET. It runs for 13 years without human intervention. Metcalfe goes on to build another ARPANET interface for Xerox PARC’s PDP-10 clone (MAXC). DEC announces the Unibus for its PDP-11 minicomputers to allow the addition and integration of myriad computer-cards for instrumentation and communications. In December, the Network Working Group (NWG) led by Steve Crocker finishes the initial ARPANET Host-to-Host protocol, called the Network Control Protocol (NCP).

 

Frank Heart puts a team together to write the software that will run the IMPs and to specify changes in the Honeywell DDP- 516 they have chosen

1969

Diagram of the first 2 nodes on the ARPANET 4-node ARPANET diagram A detail of the UCLA IMP log book, showing the successful connection to SRI

Frank Heart puts a team together to write the software that will run the IMPs and to specify changes in the Honeywell DDP- 516 they have chosen. The team includes Ben Barker, Bernie Cosell, Will Crowther, Bob Kahn, Severo Ornstein, and Dave Walden.Four sites are selected. At each, a team gets to work on producing the software to enable its computers and the IMP to communicate. At UCLA, the first site, Vint Cerf, Steve Crocker, and Jon Postel work with Kleinrock to get ready. On April 7, Crocker sends around a memo entitled ‘Request for Comments.’ This is the first of thousands of RFCs that document the design of the ARPANET and the Internet. The team calls itself the Network Working Group (RFC 10), and comes to see its job as the development of a ‘protocol,’ the collection of programs that comes to be known as NCP (Network Control Protocol). The second site is the Stanford Research Institute (SRI), where Doug Engelbart saw the ARPA experiment as an opportunity to explore wide-area distributed collaboration, using his NLS system, a prototype ‘digital library.’ SRI supported the Network Information Center, led by Elizabeth (Jake) Feinler and Don Nielson. At the University of California, Santa Barbara (UCSB) Glen Culler and Burton Fried investigate methods for display of mathematical functions using storage displays to deal with the problem of screen refresh over the net. Their investigation of computer graphics supplies essential capabilities for the representation of scientific information. After installation in September, handwritten logs from UCLA show the first host-to-host connection, from UCLA to SRI, is made on October 29, 1969. The first 'Log-In' crashes the SRI host, but the next attempt works!

 

Roberts and the ARPA team refine the overall structure and specifications for the ARPANET. They issue an RFQ for the development of the IMPs

1968

ILLIAC IV

Roberts and the ARPA team refine the overall structure and specifications for the ARPANET. They issue an RFQ for the development of the IMPs.At Bolt, Beranek and Newman (BBN), Frank Heart leads a team to bid on the project. Bob Kahn plays a major role in shaping the overall BBN designs. BBN wins the project in December. Roberts works with Howard Frank and his team at Network Analysis Corporation designing the network topology and economics. Kleinrock’s team prepares the network measurement system at UCLA, which is to become the site of the first node. The ILLIAC IV, the largest supercomputer of its time, is being built at Burroughs under a NASA contract. More than 1,000 transistors are squeezed onto its RAM chip, manufactured by the Fairchild Semiconductor Corporation, yielding 10 times the speed at one-hundredth the size of equivalent core memory. ILLIAC-IV will be hooked to the ARPANET so that remote scientists can have access to its unique capabilities.

Larry Roberts convenes a conference in Ann Arbor

1967

Paul Baran

Larry Roberts convenes a conference in Ann Arbor, Michigan, to bring the ARPA researchers together. At the conclusion, Wesley Clark suggests that the network be managed by interconnected ‘Interface Message Processors’ in front of the major computers. Called IMPs, they evolve into today’s routers.Roberts puts together his plan for the ARPANET. The separate strands of investigation begin to converge. Donald Davies, Paul Baran, and Larry Roberts become aware of each other’s work at an ACM conference where they all meet. From Davies, the word ‘packet’ is adopted and the proposed line speed in ARPANET is increased from 2.4 Kbps to 50 Kbps. The acoustically coupled modem, invented in the early sixties, is vastly improved by John van Geen of the Stanford Research Institute (SRI). He introduces a receiver that can reliably detect bits of data amid the hiss heard over long-distance telephone connections.