Course outline
Module 1
Module 1: Origins: ARPANET and Early Packet Switching
Origins: ARPANET and Early Packet Switching
Knowledge check
Q1. In what year was ARPANET's first message successfully transmitted between UCLA and the Stanford Research Institute?
- A. 1963
- B. 1969 ✓
- C. 1974
- D. 1981
Why: The first ARPANET connection linked UCLA and SRI in October 1969, when the attempted login command 'LOGIN' transmitted only the letters 'LO' before the system crashed. It marks the birth of the network that became the internet.
Q2. Which concept, independently developed by Paul Baran and Donald Davies, involves breaking messages into small blocks that travel separately across a network?
- A. Circuit switching
- B. Packet switching ✓
- C. Frequency division multiplexing
- D. Message relaying
Why: Packet switching divides data into small packets that can take different routes and be reassembled at the destination. Baran worked on this idea at RAND in the early 1960s, while Davies developed it in the UK at the National Physical Laboratory.
Q3. Which organization funded the development of ARPANET?
- A. The National Science Foundation
- B. NASA
- C. The Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense ✓
- D. IBM Research
Why: ARPANET was funded by ARPA, the U.S. Department of Defense agency later renamed DARPA. It aimed to enable resource sharing among research computers at different institutions.
Q4. What role did Interface Message Processors (IMPs) play in the original ARPANET?
- A. They stored large databases for user access
- B. They served as dedicated routers that handled packet switching between host computers ✓
- C. They encrypted all messages sent across the network
- D. They provided graphical displays for network users
Why: IMPs were minicomputers placed at each node that managed packet routing and error checking, freeing host computers from networking tasks. Bolt, Beranek and Newman (BBN) built the first IMPs.
Q5. Which early protocol, developed for ARPANET, was the forerunner of the TCP/IP suite that underpins today's internet?
- A. HTTP
- B. SMTP
- C. Network Control Protocol (NCP) ✓
- D. FTP
Why: NCP handled host-to-host communication on ARPANET in the 1970s. It was replaced by TCP/IP in January 1983, a transition that is often cited as the formal birth of the modern internet.
Module 2
Module 2: The Birth of TCP/IP and Network Protocols
The Birth of TCP/IP and Network Protocols
Knowledge check
Q1. Who are most often credited with designing the TCP/IP protocol suite in the 1970s?
- A. Tim Berners-Lee and Robert Cailliau
- B. Vint Cerf and Bob Kahn ✓
- C. Leonard Kleinrock and Larry Roberts
- D. Steve Crocker and Jon Postel
Why: Vint Cerf and Bob Kahn developed the TCP/IP design in the 1970s, publishing their foundational paper in 1974 and later refining the protocols for use on the ARPANET and beyond.
Q2. What is the main role of the Transmission Control Protocol (TCP)?
- A. Assigning IP addresses to devices on a network
- B. Translating domain names into IP addresses
- C. Providing reliable, ordered delivery of data between applications ✓
- D. Routing packets between different physical networks
Why: TCP provides reliable, ordered, and error-checked delivery of a stream of data between applications, handling retransmission of lost packets. Routing is the job of IP, and domain name translation is handled by DNS.
Q3. Which layer of the TCP/IP model is responsible for addressing and routing packets across networks?
- A. Application layer
- B. Transport layer
- C. Internet layer ✓
- D. Network access layer
Why: The Internet layer, which uses the Internet Protocol (IP), handles logical addressing and routing of packets across interconnected networks.
Q4. What was the significance of the ARPANET's adoption of TCP/IP on January 1, 1983?
- A. It was the first time email was sent between two computers
- B. It marked the official switch of the network to TCP/IP, often considered the birth of the modern Internet ✓
- C. It was when the World Wide Web was publicly launched
- D. It was the date the first domain names were registered
Why: On January 1, 1983, the ARPANET transitioned to TCP/IP as its standard protocol suite. This 'flag day' is often cited as the birth of the modern Internet because it enabled networks to interconnect using a common language.
Q5. Why was packet switching considered an important foundation for early network protocols?
- A. It required a dedicated circuit for every communication session
- B. It broke data into small packets that could travel independently and be reassembled, making networks more resilient and efficient ✓
- C. It guaranteed that all data would arrive in exactly the order it was sent
- D. It eliminated the need for any addressing system
Why: Packet switching divides messages into discrete packets that can take different routes and be reassembled at the destination. This shares network capacity efficiently and allows communication to continue even if parts of the network fail.
Module 3
Module 3: Academic Networks and the Rise of Email
Academic Networks and the Rise of Email
Knowledge check
Q1. Which early network, funded by the U.S. Department of Defense's ARPA, is generally considered the precursor to the modern Internet?
- A. NSFNET
- B. ARPANET ✓
- C. CSNET
- D. ALOHAnet
Why: ARPANET, launched in 1969, was the first operational packet-switching network and the direct ancestor of today's Internet. NSFNET and CSNET were later academic networks, and ALOHAnet was a radio-based network in Hawaii.
Q2. Who is credited with sending the first network email in 1971, and what did he use to do it?
- A. Vint Cerf, using TCP/IP
- B. Ray Tomlinson, using the @ symbol to separate user and host names ✓
- C. Tim Berners-Lee, using HTTP
- D. Larry Roberts, using the IMP
Why: Ray Tomlinson, working on ARPANET, sent the first networked email in 1971 and popularized the @ symbol to separate a user's name from their host machine's name.
Q3. What was the main purpose of CSNET, established in 1981?
- A. To provide military communications
- B. To give university computer science departments without ARPANET access a way to communicate, including via email ✓
- C. To connect home users to dial-up services
- D. To manage domain names worldwide
Why: CSNET was created by the National Science Foundation and university researchers to extend networking and email to computer science departments that lacked access to ARPANET, which was restricted to certain institutions.
Q4. Which protocol suite, standardized in the early 1980s, became the common language enabling different networks to interconnect into a 'network of networks'?
- A. FTP
- B. SMTP only
- C. TCP/IP ✓
- D. Gopher
Why: TCP/IP, developed by Vint Cerf and Bob Kahn and adopted as ARPANET's standard on January 1, 1983, allowed heterogeneous networks to interoperate, forming the basis of the Internet.
Q5. Why did early academic email systems often rely on store-and-forward delivery through intermediate hosts?
- A. Because email required physical delivery of magnetic tapes
- B. Because many machines were not always online or directly connected, so messages were held and relayed until they could reach the destination ✓
- C. Because email was encrypted and needed decryption at each stop
- D. Because the telephone network carried all email traffic
Why: Early networks had intermittent connectivity and limited direct paths between hosts, so messages were stored at intermediate machines and forwarded when a route became available, a design that shaped how SMTP still operates.
Module 4
Module 4: The World Wide Web and Tim Berners-Lee
The World Wide Web and Tim Berners-Lee
Knowledge check
Q1. In what year did Tim Berners-Lee propose the system that would become the World Wide Web while working at CERN?
- A. 1969
- B. 1980 ✓
- C. 1991
- D. 1995
Why: Berners-Lee wrote his initial proposal for information management at CERN in 1989 and built a working prototype in 1990, but his first 'Enquire' system dates back to 1980, when he developed it as a personal hypertext tool. The 1980 Enquire project is widely cited as the earliest precursor of the Web's ideas.
Q2. What does HTTP stand for in the context of the World Wide Web?
- A. HyperText Transfer Protocol ✓
- B. High Transfer Text Process
- C. HyperTerminal Transmission Port
- D. Hyperlink Text Terminal Protocol
Why: HTTP stands for HyperText Transfer Protocol, the protocol Berners-Lee designed to request and deliver web pages between a client (browser) and a server.
Q3. Which organization was Tim Berners-Lee working for when he invented the World Wide Web?
- A. MIT
- B. DARPA
- C. CERN ✓
- D. Bell Labs
Why: Berners-Lee invented the Web while working at CERN, the European Organization for Nuclear Research, in Geneva, Switzerland.
Q4. What was the name of the first web server and browser Tim Berners-Lee created?
- A. Mosaic
- B. Netscape
- C. WorldWideWeb ✓
- D. Internet Explorer
Why: Berners-Lee created the first web browser and editor, originally called 'WorldWideWeb' (later renamed Nexus to avoid confusion with the Web itself), running on a NeXT computer.
Q5. What does URL stand for?
- A. Universal Resource Locator
- B. Uniform Resource Locator ✓
- C. Unified Remote Link
- D. Universal Reference Link
Why: URL stands for Uniform Resource Locator, the address format used to identify and locate resources such as web pages on the Internet.
Module 5
Module 5: The Browser Wars and Commercial Expansion
The Browser Wars and Commercial Expansion
Knowledge check
Q1. Which browser's dominance in the mid-1990s sparked the United States v. Microsoft antitrust case?
- A. Netscape Navigator ✓
- B. Mosaic
- C. Opera
- D. Lynx
Why: Netscape Navigator held the majority of the browser market in the mid-1990s. Microsoft's bundling of Internet Explorer with Windows led to the antitrust lawsuit, which focused on how Microsoft used its operating system monopoly to crush Netscape.
Q2. What was the name of the graphical web browser released in 1993 that helped popularize the World Wide Web?
- A. Mosaic ✓
- B. WorldWideWeb
- C. Gopher
- D. Archie
Why: NCSA Mosaic, released in 1993, was one of the first widely used graphical browsers. It displayed images inline with text, making the web accessible to non-technical users and paving the way for commercial browsers.
Q3. What was the term for Microsoft's practice of including Internet Explorer for free with the Windows operating system?
- A. Open sourcing
- B. Bundling ✓
- C. Licensing
- D. Outsourcing
Why: Bundling refers to packaging products together. By including Internet Explorer with Windows at no extra cost, Microsoft made it the default choice for most users, which critics argued was anticompetitive.
Q4. Which company's 1995 initial public offering is often cited as a catalyst for the dot-com boom?
- A. Amazon
- B. Netscape Communications ✓
- C. Google
- D. Yahoo
Why: Netscape's IPO in August 1995 saw its stock price soar far above expectations on the first day of trading. This strong investor enthusiasm for internet companies helped launch the late-1990s dot-com investment frenzy.
Q5. Which early browser was developed by Marc Andreessen and Eric Bina at the University of Illinois before they founded Netscape?
- A. Internet Explorer
- B. Mosaic ✓
- C. Safari
- D. Firefox
Why: Marc Andreessen and Eric Bina developed NCSA Mosaic at the National Center for Supercomputing Applications. Andreessen then co-founded Netscape, bringing Mosaic's ideas into a commercial product.
Module 6
Module 6: Dot-Com Boom, Bust, and Broadband
Dot-Com Boom, Bust, and Broadband
Knowledge check
Q1. Which event is most often cited as marking the start of the dot-com boom's peak in investor enthusiasm?
- A. The launch of the World Wide Web in 1991
- B. Netscape's IPO in August 1995 ✓
- C. The passage of the Telecommunications Act of 1996
- D. The release of Windows 95 in 1995
Why: Netscape's successful IPO in August 1995 saw its share price nearly double on the first day, signaling intense investor appetite for internet companies and kicking off the dot-com frenzy.
Q2. What was the NASDAQ Composite index's approximate peak in March 2000 before the dot-com crash?
- A. About 1,000 points
- B. About 2,500 points
- C. About 5,000 points ✓
- D. About 10,000 points
Why: The NASDAQ Composite peaked at roughly 5,000 points in March 2000, and then lost about 78 percent of its value by October 2002 as the bubble burst.
Q3. What does the term 'burn rate' refer to in the context of dot-com startups?
- A. The speed at which a website loaded pages
- B. The rate at which a company spent its cash reserves ✓
- C. The percentage of users who abandoned a shopping cart
- D. The number of servers a company needed to run
Why: Burn rate measures how quickly a company spends its cash. Many dot-com startups had high burn rates while prioritizing user growth over revenue, and they ran out of money when investors stopped funding them.
Q4. Which technology made high-speed 'always-on' home internet access widely available in the early 2000s, following the dial-up era?
- A. Satellite television
- B. Broadband via DSL and cable modem ✓
- C. Fiber optic cables to every home in the United States
- D. Wireless 3G mobile phones
Why: DSL over telephone lines and cable modems over television networks became the dominant broadband technologies in the early 2000s, offering always-on connections far faster than dial-up.
Q5. Which company, despite surviving the dot-com bust, saw its stock fall about 90 percent from its 2000 peak and later recovered to become one of the world's most valuable companies?
- A. Pets.com
- B. Webvan
- C. Amazon ✓
- D. eToys
Why: Amazon's stock dropped roughly 90 percent after the 2000 peak, but the company survived by focusing on profitability and continued growth, eventually becoming one of the most valuable companies in the world. Pets.com, Webvan, and eToys all failed.
Module 7
Module 7: Social Media, Mobile, and the Modern Internet
Social Media, Mobile, and the Modern Internet
Knowledge check
Q1. Which platform, launched in 2004 by a Harvard student, became one of the first major social networks to reach mass popularity among college students?
- A. MySpace
- B. Facebook ✓
- C. Friendster
- D. Orkut
Why: Facebook was launched in 2004 by Mark Zuckerberg and initially restricted membership to Harvard students before expanding to other colleges and eventually the general public.
Q2. What social media feature, introduced by Twitter, limited posts to a specific number of characters?
- A. Hashtags
- B. Retweets
- C. Tweets ✓
- D. Threads
Why: Twitter's original posts, called tweets, were limited to 140 characters, a constraint partly inspired by SMS text message limits.
Q3. Which event in 2007 is widely considered a turning point that accelerated the rise of mobile internet use?
- A. Release of the first Android phone
- B. Launch of the original iPhone ✓
- C. Introduction of 3G networks in Europe
- D. Creation of the mobile web standard WAP
Why: Apple's iPhone, released in 2007, combined a full touchscreen web browser with an app-friendly design, helping make smartphones mainstream and internet access on mobile devices common.
Q4. What term describes the practice of sharing user-generated photos and updates with a broad audience through apps like Instagram, which emphasized visual content and filters?
- A. Blogging
- B. Microblogging ✓
- C. Podcasting
- D. Vlogging
Why: Microblogging refers to short-form posts, and while Twitter is the classic example, Instagram-style visual sharing is often grouped with social media that emphasizes brief, frequent updates. Note that the term most directly describes short text posts such as tweets.
Q5. Which company acquired Instagram in 2012 for approximately $1 billion?
- A. Google
- B. Microsoft
- C. Facebook ✓
- D. Yahoo
Why: Facebook acquired Instagram in 2012 for roughly $1 billion in cash and stock, bringing the popular photo-sharing app under its umbrella.