16

2. Compare circuit- and packet-switched networks.

Old phone systems use a technology called circuit switching. A "circuit" is a dedicated connection between two entities. In a circuit-switched network, a call results in a circuit being opened, dedicating a specific amount of capacity between the communicating parties. The users are using that "circuit" regardless of whether they are talking or not. Internet networks are packet-switched networks and these can be more efficient. Since conversations can be sliced up into packets, they can be squeezed into smaller spaces. If there are pauses in a conversation or someone's on hold, applications don't hold up the network. And that creates an opportunity to use the network's available capacity for other users. The trade off is one that swaps circuit-switching quality of service (QoS) with packet switching's efficiency and cost savings.

2. The protocol used for exchange of mail between e-mail servers across the world is called _____.

Simple Mail Transfer Protocol (SMTP)

1. The term __________ refers to frequencies used for wireless communication.

Spectrum

2. Briefly describe how the DNS helps users communicate with each other.

The domain name service is a distributed database that looks up the host and domain names that a user enters and returns the actual IP address for the computer that the user wants to communicate with. It's like a big, hierarchical set of phone books (called nameservers) capable of finding Web servers, e-mail servers, and more. When a user enters a Web address, the computer connects to the DNS resolver, the function of which is to start a lookup for the address. The resolver starts at one of the thirteen root nameservers, which, in turn, points the resolver to the top level domain nameserver. This lookup is repeated for the domain name and host name and finally the IP address for the combination is located and passed onto the computer. Thus, the user's computer is ready to communicate with the computer hosting the Web site.

10. IP addresses can oftentimes be used to identify a user's geographic location.

True

2. The Internet has no center and no one owns it.

True

3. Many residential providers of cable technology use a system that requires customers to share bandwidth with neighbors.

True

4. DSL technology is less efficient for service providers in the United States because many of their customers are live in less-densely populated suburbs and rural areas.

True

5. Changing the letter case when typing in host and domain names does not affect the user's ability to reach the destination.

True

5. Many fear that innovation might suffer as a result of the transition of Internet services from flat-rate pricing to metered usage.

True

5. The TCP works at both ends of Internet communication.

True

6. The User Datagram Protocol (UDP) acts as a substitute to TCP when there is a need for speed of communication, but where perfect and complete transmission quality can be sacrificed.

True

7. Servers or organizations do not need to be housed within a country in order to use a country code as part of their domain name.

True

8. A device gets its IP address from whichever organization is currently connecting it to the Internet.

True

9. Computer programs making decisions without any human intervention conduct most U.S. stock trading.

True

9. Unfortunately, IPv6 isn't backward compatible with IPv4.

True

7. Circuit-switched networks provide connection between two parties that: a. uses a single router for each individual on either end of the connection. b. is dedicated for use by the parties for the duration of a connection. c. repeatedly switches between an open and closed state depending on whether someone is speaking or other noise is being transmitted during a call. d. slicing up the conversation into smaller chunks and transmitting them over a shared circuit that mixes content with other callers but routes and reassembles a call to the correct recipient. e. prioritizing voice calls over other connections on IP networks.

b

8. What is an example of cybersquatting? a. Overwhelming a firm's Web site by flooding it with seemingly legitimate messages b. Acquiring a domain name to extort a firm, individual, product, or trademark holder c. Slowing down packet transfer to an Internet-connected computer d. Threatening to destroy information stored in a firm's servers e. Hacking into and defacing an organization's public web presence and refusing to let the site's owner regain control

b

9. "Html" is used to: a. load content from default page. b. create and format Web pages. c. generate custom content for database users. d. exchange mail with other e-mail servers. e. transfer files from flash drives.

b

2. Internet services that run at download speeds of a minimum of 25 mbps and upload speeds of three mbps are called ____________.

broadband

12. To overcome reception and availability problems, mobile telecom services firms have begun _____ that provide a "five bar" coverage in a roughly 5,000-square-foot footprint. a. providing incentives to communities that allow the construction of towers b. leveraging GEO and LEO technologies c. offering femtocells d. providing wi-fi base stations at very low costs e. switching from Wi-Fi to WiMax

c

3. One of the disadvantages of cable technology is that: a. it is more expensive than other signal-carrying systems. b. while it works well for television signals, it is ineffective for data transmissions required by the Internet. c. systems used by many providers require customers to share bandwidth with neighbors. d. it is incompatible with most modern communication systems. e. the speed of the connection rises in conjunction with the distance between the end customers from the central hub.

c

3. Which of the following statements holds true for the term "html"? a. It refers to high-speed data lines provided by many firms all across the world that interconnect and collectively form the core of the Internet. b. It refers to the broadband service provided via light-transmitting fiber-optic cables. c. It refers to the language used to create and format Web pages. d. It refers to a situation when separate ISPs link their networks to swap traffic on the Internet. e. It refers to a system that connects end users to the Internet.

c

4. A _____ enables communication by defining the format of data and rules for exchange. a. nomenclature b. regulation c. protocol d. dialect e. convention

c

7. The frequencies licensed by telecommunication firms to provide wireless service is known as _____. a. GEO and LEO range b. mobile service array c. wireless spectrum d. communication backbone e. communication bandwidth

c

9. Which of the following refers to wireless systems provided by earth-bound stations like cell phone towers? a. Geostationary wireless b. Ground wireless c. Terrestrial wireless d. Geosynchronous wireless e. LEO systems

c

3. A location where gear from multiple telecom firms can come together and peering can take place.

colocation

10. The acronym HFT refers to: a. High Finance Telecommunications b. High Fidelity Transmissions c. Hedge Fund Transfers d. High Frequency Trading e. Hypertext File Transfer

d

11. Supporters of net neutrality believe: a. it will improve innovation. b. it will keep costs low. c. it will level the playing field among competitive services offered over the Internet. d. all of the above. e. none of the above.

d

12. The fault-tolerant nature of the DNS ensures that: a. if users can't reach a host computer, they are redirected back to the previous page. b. mistyped or misspelled Web addresses are automatically corrected. c. if a document or file can't be accessed, it won't result in a 404 error. d. the service continues functioning even if one nameserver goes down. e. mismatched host names and domain names are still assigned with the correct IP address. d

d

13. The exploit referred to as __________ allowed hackers to leverage vulnerability in DNS software to redirect users to sites they did not request. a. cybersquatting. b. phishing. c. an online imposture. d. cache poisoning. e. a distributed denial of request.

d

4. Internet networks are _____. a. bit-switched networks b. circuit-switched networks c. data-switched networks d. packet-switched networks e. byte-switched networks

d

5. Peering refers to: a. high-speed data lines provided by many firms all across the world that interconnect and collectively form the core of the Internet. b. the broadband service provided via light-transmitting fiber-optic cables. c. the language used to compose Web pages. d. a situation when separate ISPs connect their networking equipment together to share traffic. e. a system that connects end users to the Internet.

d

7. A firm that provides hardware and services to run Web sites of others is known as a(n) _____. a. Web site incubator b. Internet service facilitator c. Web domain name registrar d. Web hosting service e. Internet Web fab

d

8. Peering usually takes place at neutral sites called _____. a. https b. IPs c. ISPs d. IXPs e. STPs

d

1. One of the factors that accelerated the development of the Internet during the 1990s was: a. the introduction of the personal computer into households. b. the government's taking over of the Internet's operating structure from private players. c. Intel's invention of low power processors used in portable computers. d. the creation of the Windows and Mac OS operating systems. e. the invention of graphical Web browsing.

e

1. The Internet Protocol Suite consists of the Internet Protocol and _____. a. File Transfer Protocol b. Simple Mail Transfer Protocol c. Session Initiation Protocol d. Datagram Congestion Control Protocol e. Transmission Control Protocol

e

10. The domain name service (DNS) is a distributed database that allows users to communicate with other computers by: a. assigning IP addresses to different domain names. b. mapping host names to domain names. c. creating IP addresses that are unique to servers. d. assigning domain names to different IP addresses. e. mapping host and domain names to IP addresses of computers.

e

3. Which of the following applications is most likely to use UDP instead of TCP? a. E-mail b. Web transmissions c. File transfer d. Peer-to-peer downloads e. Web-based phone calls

e

6. Popular sites like Google and Yahoo! have several computers assigned to their host names because: a. they have operations in different countries. b. they are registered under several generic top-level domain names. c. of the different devices used to access these web sites. d. hoarding all information in one server is expensive. e. it ensures that the load of requests to their sites do not overwhelm a single computer.

e

6. _____ involves allowing voice packets to gain delivery importance over packets for applications like e-mail. a. Voice precedence b. Data rationing c. Right-of-way for voice d. Information queuing e. Packet prioritization

e

8. The most dominant standard for 4G technology worldwide is a. Wi-Fi b. WiMax c. GPRS d. Circuit switching e. LTE

e

9. ____ repeatedly sends a cluster of three packets starting at the first router connected to a computer, then the next, and so on, building out the path that packets take to their destination. a. Firewall b. Router c. Pathfinder d. Mapper e. Traceroute

e

2. Routing protocol that is in charge of forwarding packets on the Internet is known as voice over Internet protocol.

false

4. The phrase ________ is used by technologists to refer to delay.

latency

2. _____ is the principle that all Internet traffic should be treated equally.

net neutrality

5. A technique known as _____ uses a gateway that allows multiple devices to share a single IP address. This can be useful in organizations that have a limited number of conventional IP addresses.

network address translation/NAT

2. A unit of data forwarded by a network is called _____.

packet

1. A(n) _____ is a computing device that connects networks and exchanges data between them.

router

1. Routers don't have perfect, end-to-end information on all points in the Internet.

true

1. Identify the various components in the following Web address and briefly describe each of them: http://en.wikipedia.org/wiki/Web_address

"http" is the application transfer protocol used in the Web address and stands for "hypertext transfer protocol." The http protocol defines how Web browser and Web servers communicate and is designed to be hardware and operating system independent. 'en' refers to the host name indicating the computer hosting the Web site. The host name is assigned an IP address which helps locate the host computer. "wikipedia" refers to the domain name and ".org" is the top-level domain. "wiki" is the path that maps to the folder location where the file is stored under the filename "Web_address."

3. _____ Law states that a system's speed is determined by its slowest component.

Amdahl's

3. The three letter acronym for the basic unit of expression for bandwidth is _____.

Bits per second/BPS

1. Briefly describe a few of the measures being taken to speed up the Internet's last mile

Cable broadband: Uses a thick copper wire to offer broadband access. That wire (called a coaxial cable or coax) has shielding that reduces electrical interference, allowing cable signals to travel longer distances without degrading and with less chance of interference than conventional telephone equipment. Digital Subscriber Line (DSL): DSL technology uses the copper wire that phone companies have already run into most homes. Fiber to the Home: Uses optic fibers to transmit data in the form of light. It is the fastest last-mile technology around. It is capable of serving extremely high speeds of over 50 Mbps and can also work over long distances.

1. Most mobile large cell phone carriers are exempted from having to license the wireless spectrum for transmission.

False

1. When the Internet really took off, much of the Internet's operating infrastructure transitioned to be supported by government grants rather than private firms.

False

2. When considering overall network speed, a system's speed is determined by its fastest component.

False

3. In the URL, the host name is the name of the network a user tries to connect to.

False

3. Wall Street traders often choose a colocation facility with the goal to provide high-latency connectivity to their partners.

False

4. TCP and IP operate above http and the other application transfer protocols

False

4. The language "http" is used to create and format Web pages.

False

6. Dot-com domain name registration is carried out on an auction basis to ensure the highest bidder gains rights to the desired domain name.

False

7. Circuit-switched networks are advantageous because they offer an inexhaustible supply of bandwidth for telecommunications.

False

8. ISPs and IXPs that carry out peering are required by the FCC to charge each other fees based on their traffic contribution.

False

4. _____ refers to the application transfer protocol that is used to copy files from one computer to another.

File transfer protocol

3. _____ is the language used to compose Web pages.

HTML/ hypertext markup language

1. _____ is the nonprofit organization responsible for managing the Internet's domain and numbering systems.

ICANN/internet corporation for assigned names and numbers

4. Which technology—LEO or GEO satellites—offers lower latency?

LEO

1. Describe the process involving the transmission of a Web page from a Web server to a user's computer.

TCP and IP operate below http and the other application transfer protocols. TCP works its magic at the start and endpoint of the trip—on both the user's computer and on the destination computer they're communicating with. If a Web server wants to send the user a large Web page, the Web server application hands the Web page it wants to send to its own version of TCP. TCP then slices the Web page up into smaller chunks of data called packets (datagrams). The packets are like little envelopes containing part of the entire transmission—they're labeled with a destination address and a source address. The TCP on the Web server hands over these packets to the IP. The IP routes the packets to their final destination, and these packets might have to travel over several networks to get to where they're going. The relay work is done via special computers called routers, and these routers speak to each other and to other computers using IP. Once the transmitted packets are received by the destination computer, that machine's version of TCP takes over by checking to make sure that it has all of the packets it was sent and that no packets were damaged or corrupted. It also requests replacement packets (if needed), and then puts the packets in the correct order, passing a perfect copy of the transmission.

2. Explain the evolution of satellite wireless telecommunication technology.

Wireless systems provided by earth-bound base stations like cell phone towers are referred to as terrestrial wireless, but it is possible to provide telecommunications services via satellite. The first residential satellite services were download-only, while one still needed a modem or some other connection to send any messages from their PC to Internet. Many early systems also required large antennas and were quite expensive. Finally, some services were based on satellites in geosynchronous earth orbit (GEO). GEO satellites circle the earth in a fixed, or stationary orbit above a given spot on the globe, but in order to do so they're positioned out at a distance roughly the equivalent of the planet's circumference. Recent developments in satellite wireless technology include an effort by a firm named O3b Networks, which thinks it might have solved the challenges that plagued early pioneers. O3b stands for the "Other 3 Billion" of the world's population who lack broadband Internet access, and the firm hopes to provide "fiber-quality" wireless service to more than 150 countries, specifically targeting underserved portions of the developing world. These 'middle earth orbit' satellites will circle closer to the earth to reduce latency (only about 5,000 miles up, less than 1/4th the distance of GEO systems).

1. Which of the following is true of the term Internet backbone? a. It refers to high-speed data lines provided by many firms all across the world that interconnect and collectively form the core of the Internet. b. It refers to broadband service provided direct to a home or business using light-transmitting fiber-optic cables. c. It refers to the collection of standards used to support all Internet services. d. It refers to government-provided open spectrum that enables Internet use for all. e. It refers to a government-run system supported by telecommunication taxes, which connects end users to the Internet.

a

10. Mobile providers can be susceptible to poor coverage indoors as a result of: a. spectrum used by most mobile phone firms that does not travel well through solid objects. b. a high degree of latency. c. network congestion that clogs up the network traffic. d. a lack of sufficient number of towers owing to the not-in-my-backyard problem. e. an increase in bandwidth demand placed on their networks.

a

11. A(n) _____ is a temporary storage space used to speed computing tasks. a. cache b. IP address c. Protocol d. domain name service e. hypertext markup language

a

2. One of the functions of the IP is to: a. route message packets to the final destination. b. slice up the message into smaller chunks of data called packets, to be sent over the network. c. check for damaged or corrupt message packets and request for replacements, if needed. d. label message packets with source and destination addresses. e. rearrange message packets in the same sequence as they were sent.

a

5. The hypertext transfer protocol (http) defines the communication between: a. Web browsers and Web servers. b. operating systems and Web browsers. c. hardware and operating systems. d. mail servers and hardware. e. hardware and Web browsers.

a

6. A potential roadblock to transition of DSL to FTTH is the: a. high costs of building entirely new networks. b. scarcity of the material required to create the cables. c. impracticality of switching to a technology that is not proven yet. d. location driven quality of service offered by fiber optic technology. e. high possibility of external interference and hence, fears of information security.

a

2. The address one types into a Web browser is also known as a: a. universal redirection link. b. uniform resource locator. c. unique resource locator. d. universal redirection locator. e. uniform resource link.

b

2. _____ is the insulated copper cable commonly used by cable television providers with shielding to reduce electrical interference. a. Optical fiber cable b. Coaxial cable c. Ribbon cable d. FTTH cable e. Amdahl cable

b

4. _____ technology is a broadband technology that can use the wires of a local telephone network. a. Fiber to the Home (FTTH) b. Digital Subscriber Line (DSL) c. Coaxial cable d. Telecom-broadband hybrid e. Broadband over power line (BPL)

b

5. Which of the following statements is true of the term "FTTH"? a. It refers to high-speed data lines provided by many firms all across the world that interconnect and collectively form the core of the Internet. b. It refers to broadband service provided via light-transmitting fiber-optic cables. c. It refers to the language used to compose Web pages. d. It refers to a situation when separate ISPs link their networks to swap traffic on the Internet. e. It refers to a system that connects end users to the Internet.

b