Although the 1960s were the decade of the mainframe, the 1970s gave birth to Ethernet, which today is by far the most popular LAN technology. Ethernet was born in 1973 in Xerox Corporation's research lab in Palo Alto, California. (An earlier experimental network called ALOHAnet was developed in 1970 at the University of Hawaii.) The original Xerox networking system was known as X-wire and worked at 2.94 Mbps. X-wire was experimental and was not used commercially, although a number of Xerox Palo Alto workstations used for word processing were networked together in the White House using X-wire during the Carter administration. In 1979, Digital Equipment Corporation (DEC), Intel, and Xerox formed the DIX consortium and developed the specification for standard 10-Mbps Ethernet, or thicknet, which was published in 1980. This standard was revised and additional features were added in the following decade.
The conversion of the backbone of the Bell telephone system to digital circuitry continued during the 1970s and included the deployment in 1974 of the first digital data service (DDS) circuits (then called the Dataphone Digital Service). DDS formed the basis of the later deployment of ISDN and T1 lines to customer premises, and AT&T installed its first digital switch in 1976.
In wide area networking, a new telecommunications service called X.25 was deployed toward the end of the decade. This new system was packet-switched, in contrast to the circuit-switched PSTN, and later evolved into public X.25 networks such as GTE's Telenet Public Packet Distribution Network (PDN), which later became SprintNet. X.25 was widely deployed in Europe, where it still maintains a large installed base, especially for communications in the banking and financial industry.
In 1970 the Federal Communications Commission (FCC) announced the regulation of the fledgling cable television industry. Cable TV remained primarily a broadcast technology for delivering entertainment to residential homes until the mid-1990s, when technologies began to be developed to enable it to carry broadband services to residential subscribers. Cable modems now compete strongly with Digital Subscriber Line (DSL) as the main two forms of broadband Internet access technologies.
Despite all these technological advances, however, telecommunications services in the 1970s remained unintegrated, with voice, data, and entertainment carried on different media. Voice was carried by telephone, which was still analog at the customer premises; entertainment was broadcast using radio and television technologies; and data was usually carried over RS-232 or Binary Synchronous Communication (BSC) serial connections between dumb terminals and mainframes (or, for remote terminals, long-haul modem connections over analog telephone lines).
The 1970s were also notable for the growth of ARPANET, which grew throughout the decade as additional hosts were added at various universities and government institutions. By 1971 the network had 19 nodes, mostly consisting of a mix of PDP-8, PDP-11, IBM
S/360, DEC-10, Honeywell, and other mainframe and minicomputer systems linked together. The initial design of ARPANET called for a maximum of 265 nodes, which seemed like a distant target in the early 1970s. The initial protocol used on this network was NCP, but this was replaced in 1982 by the more powerful TCP/IP protocol suite. In 1975 the administration of ARPANET came under the authority of the Defense Communications Agency.
ARPANET protocols and technologies continued to evolve using the informal RFC process developed in 1969. In 1972 the Telnet protocol was defined in RFC 318, followed by FTP in 1973 (RFC 454). ARPANET became an international network in 1973 when nodes were added at the University College of London in the United Kingdom and at the Royal Radar Establishment in Norway. ARPANET even established an experimental wireless packet-switching radio service in 1977, which two years later became the Packet Radio Network (PRNET).
Meanwhile, in 1974 the first specification for the Transmission Control Protocol (TCP) was published. Progress on the TCP/IP protocols continued through several iterations until the basic TCP/IP architecture was formalized in 1978, but it was not until 1983 that ARPANET started using TCP/IP instead of NCP as its primary networking protocol.
The year 1977 also saw the development of UNIX to UNIX Copy (UUCP), a protocol and tool for sending messages and transferring files on UNIX-based networks. An early version of the USENET news system using UUCP was developed in 1979. (The Network News Transfer Protocol [NNTP] came much later, in 1987.)
In 1979 the first commercial cellular phone system began operation in Japan. This system was analog in nature, used the 800-MHz and 900-MHz frequency bands, and was based on a concept developed in 1947 at Bell Laboratories.
An important standard to emerge in the 1970s was the public-key cryptography scheme developed in 1976 by Whitfield Diffie and Martin Hellman. This scheme underlies the Secure Sockets Layer (SSL) protocol developed by Netscape Communications, which is still the predominant approach for ensuring privacy and integrity of financial and other transactions over the World Wide Web (WWW). Without SSL, popular e-business sites such as Amazon and eBay would have a hard time attracting customers!
Among other miscellaneous developments during this decade, in 1970 IBM researchers invented the relational database, a set of conceptual technologies that has become the foundation of today's distributed application environments. In 1971, IBM demonstrated the first speech recognition technologies--which have since led to those annoying automated call handling systems found in customer service centers! IBM also developed the concept of the virtual machine in 1972 and created the first sealed disk drive (the Winchester) in 1973. In 1974, IBM introduced the Systems Networking Architecture (SNA) for networking its mainframe computing environment. In 1971, Intel released its first microprocessor, a 4-bit processor called the 4004 that ran at a clock speed of 108 kilohertz (kHz), a snail's pace by modern standards but a major development at the time. Another significant event was the launching of the online service CompuServe in 1979, which led to the development of the first online communities.
The first personal computer, the Altair, went on the market as a kit in 1975. The Altair was based on the Intel 8080, an 8-bit processor, and came with 256 bytes of memory, toggle switches, and light-emitting diode (LED) lights. Although the Altair was basically for hobbyists, the Apple II from Apple Computer, which was introduced in 1977, was much more. A typical Apple II system, which was based on the Motorola 6502 8-bit processor, had 4 KB of RAM, a keyboard, a motherboard with expansion slots, built-in BASIC in ROM, and color graphics. The Apple II quickly became the standard desktop system in schools and other educational institutions. A physics classroom I taught in had one all the way into the early 1990s (limited budget!). However, it was not until the introduction of the IBM Personal Computer (PC) in 1981 that the full potential of personal computers began to be realized, especially in businesses.
In 1975, Bill Gates and Paul Allen licensed their BASIC computer programming language to MITS, the Altair's manufacturer. BASIC was the first computer language specifically written for a personal computer. Gates and Allen coined the name "Microsoft" for their business partnership, and they officially registered it as a trademark the following year. Microsoft Corporation went on to license BASIC to other personal computing platforms such as the Commodore PET and the TRS-80. I loved BASIC in those early days, and I still do!
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