1.7 Internet and World Wide Web

In the late 1960s, ARPA—the Advanced Research Projects Agency of the United States Department of Defense—rolled out plans for networking the main computer systems of approximately a dozen ARPA-funded universities and research institutions. The computers were to be connected with communications lines operating at speeds on the order of 50,000 bits per second, a stunning rate at a time when most people (of the few who even had networking access) were connecting over telephone lines to computers at a rate of 110 bits per second. Academic research was about to take a giant leap forward. ARPA proceeded to implement what quickly became known as the ARPANET, the precursor to today’s Internet. Today’s fastest Internet speeds are on the order of billions of bits per second with trillion-bits-per-second speeds on the horizon!

Things worked out differently from the original plan. Although the ARPANET enabled researchers to network their computers, its main benefit proved to be the capability for quick and easy communication via what came to be known as electronic mail (e-mail). This is true even on today’s Internet, with e-mail, instant messaging, file transfer and social media such as Facebook and Twitter enabling billions of people worldwide to communicate quickly and easily.

The protocol (set of rules) for communicating over the ARPANET became known as the Transmission Control Protocol (TCP). TCP ensured that messages, consisting of sequentially numbered pieces called packets, were properly routed from sender to receiver, arrived intact and were assembled in the correct order.

The Internet: A Network of Networks

In parallel with the early evolution of the Internet, organizations worldwide were implementing their own networks for both intraorganization (that is, within an organization) and interorganization (that is, between organizations) communication. A huge variety of networking hardware and software appeared. One challenge was to enable these different networks to communicate with each other. ARPA accomplished this by developing the Internet Protocol (IP), which created a true “network of networks,” the current architecture of the Internet. The combined set of protocols is now called TCP/IP.

Businesses rapidly realized that by using the Internet, they could improve their operations and offer new and better services to their clients. Companies started spending large amounts of money to develop and enhance their Internet presence. This generated fierce competition among communications carriers and hardware and software suppliers to meet the increased infrastructure demand. As a result, bandwidth—the information-carrying capacity of communications lines—on the Internet has increased tremendously, while hardware costs have plummeted.

The World Wide Web: Making the Internet User-Friendly

The World Wide Web (simply called “the web”) is a collection of hardware and software associated with the Internet that allows computer users to locate and view multimedia-based documents (documents with various combinations of text, graphics, animations, audios and videos) on almost any subject. In 1989, Tim Berners-Lee of CERN (the European Organization for Nuclear Research) began developing HyperText Markup Language (HTML)—the technology for sharing information via “hyperlinked” text documents. He also wrote communication protocols such as HyperText Transfer Protocol (HTTP) to form the backbone of his new hypertext information system, which he referred to as the World Wide Web.

In 1994, Berners-Lee founded the World Wide Web Consortium (W3C, http://www.w3.org), devoted to developing web technologies. One of the W3C’s primary goals is to make the web universally accessible to everyone regardless of disabilities, language or culture.

Web Services

Web services are software components stored on one computer that can be accessed by an app (or other software component) on another computer over the Internet. With web services, you can create mashups, which enable you to rapidly develop apps by combining complementary web services, often from multiple organizations, and possibly other forms of information feeds. For example, 100 Destinations (http://www.100destinations.co.uk) combines the photos and tweets from Twitter with the mapping capabilities of Google Maps to allow you to explore countries around the world through the photos of others.

ProgrammableWeb (http://www.programmableweb.com/) provides a directory of over 15,000 APIs and 6,200 mashups, plus how-to guides and sample code for creating your own mashups. According to Programmableweb, the three most widely used APIs for mashups are Google Maps, Twitter and YouTube.

Ajax

Ajax technology helps Internet-based applications perform like desktop applications—a difficult task, given that such applications suffer transmission delays as data is shuttled back and forth between your computer and server computers on the Internet. Using Ajax, applications like Google Maps have achieved excellent performance, approaching the look-and-feel of desktop applications.

The Internet of Things

The Internet is no longer just a network of computers—it’s an Internet of Things. A thing is any object with an IP address—a unique identifier that helps locate that thing on the Internet—and the ability to send data automatically over the Internet. Such things include:

  • a car with a transponder for paying tolls,

  • monitors for parking-space availability in a garage,

  • a heart monitor implanted in a human,

  • monitors for drinkable water quality,

  • a smart meter that reports energy usage,

  • radiation detectors,

  • item trackers in a warehouse,

  • mobile apps that can track your movement and location,

  • smart thermostats that adjust room temperatures based on weather forecasts and activity in the home

  • and many more.

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