cis 3220

Ch1




















Modern (1990s and beyond) data communication networks are characterized by:




Sel

distributed systems that rely heavily on networking







In 1983, the Internet was split into two parts, one dedicated solely to the military and one dedicated to university research centers. The two parts were called:





Milnet and Internet







Which of the following is not true about a server?




can only perform one function on a network.







Networks that are designed to connect similar computers that share data and software with each other are called:





peer-to-peer networks







The function of the file server is to





store data and software programs that can be used by client computers on the network.







A local area network is:





a group of personal computers or terminals located in the same general area and connected by a common cable (communication circuit) so they can exchange information.







A backbone network is:





a high speed central network that connects other networks in a distance spanning up to several miles.







A metropolitan area network is:





a network that spans a geographical area that usually encompasses a city or county area (3 to 30 miles) and that typically uses common carrier circuits.







Which of the following is not a property of a WAN:





connects a group of computers in a small geographic area such as room, floor, building or campus.







Which layer of the OSI model is responsible for ensuring that all packets sent are received by the destination station by dealing with end-to-end issues?





transport Layer





Which layer of the OSI model is responsible for ensuring flow control so that the destination station does not receive more packets that it can process at any given time?




transport Layer







The presentation _ layer of the OSI model is responsible for data format translation.












In the Internet model, the application layer corresponds to the ________, layer(s) s of the OSI model.




session, presentation and application







Which is not a function of the physical layer:





providing error-free transmission of dat







The _________ layer is responsible for routing of messages from the sender to the final destination.





network layer





Which of the following is not a function of the data link layer?




specifying the type of connection, and the electrical signals, radio waves, or light pulses that pass through it







Which of the following is a function of the transport layer?




breaking long messages into several smaller messages






Which of the following is a term used to group together the physical and data link layers?




Hardware layers






Which of the following would be a standard used at the Data Link layer of the Internet or OSI model?




Ethernet






In which layer of the Internet model would the HTTP standard be used?




application






A(n) _ protocol _ is a set of rules that determine what a layer would do and provides a clearly defined set of messages that software at the layer needs to understand.











The network layer of the Internet model uses the _____ip_ protocol to route messages though the network.











The primary reason for networking standards is to:




ensure that hardware and software produced by different vendors can work together







Which of the following is not true about de juro standards?




They are always developed before de facto standards.







Which of the following is not true about de facto standards?




They never evolve into de juro standards.







The three stages of the de juro standardization process are ______________________.




specification, identification of choices and acceptance.













Which of the following is not true about ITU-T:




Its membership is limited to U.S. telephone companies







The internet standards organization that will allow anyone to join is ___ IETF ______.











Which standards body is responsible for the development of local area network (LAN) standards?




IEEE







Which of the following is not an important future trend in communication and networking?




development of online batch systems







The integration of voice, video, and data communications is also known as convergence__.























A(n__________ is the way in which the functions of the application layer software are spread among the clients and servers in the network.

application architecture

A ________ is a very large general-purpose computer that is capable of performing very many functions as if these are done simultaneously, and storing extremely large amounts of data

mainframe

A ________ is a group of computers linked together so that they act as one computer.

server farm

With the two-tier client-server architecture, the server is responsible for the ________ logic.

data access

Which of the following is not a general function by any application program?

application access storage

_________ is an application program function that deals with storing and retrieving dat

data storage

An application program function is __________, or the processing required to access dat

data access logic

______________, or the algorithms or business logic programmed into the application, can be simple or complex depending on the application.

application logic

________ is the presentation of information to the user and the acceptance of the user’s commands.

presentation logic

One underlying problem with a host-based network is that:

the server can get overloaded since it must process all messages

With a client-based network, one fundamental problem is that:

all data on the server must travel to the client for processing

With the two-tier client-server architecture, the client is responsible for the ________ logic.

presentation

Client-server architectures:

can use middleware to provide a standard way of communicating between software from more than one vendor

How are the application architecture functions split up in a client-server network?

the presentation logic is on the client, while the data storage and data access logic are on the server

In a client-server network, _________ gets software from different vendors to work together.

middleware

____________ is not an important middleware standard.

Asynchronous Transfer Mode (ATM)

In the three tier architecture, the software on the client computer is responsible for the ____________.

presentation logic

An N-tiered architecture:

is generally more “scalable” than a three-tiered architecture

One disadvantage of the ____________ architecture is that places a greater load on the network.

n-tier

A “thin client” architecture approach:

places all or almost all of the application logic on the server

A “thick client” architecture approach:

places all or almost all of the application logic on the client

With the “thin client” architecture, when an application changes, only the _________ with the application logic needs to be updated.

server

The idea for a special hypertext network, called the World Wide Web, was conceived of by:

Tim Berners-Lee at the European Laboratory for Particle Physics (CERN) in 1989

Marc Andreessen led a team that developed the first graphical Web browser, which was called:

Mosaic

To interact with the World Wide Web, a client computer needs an application layer software package called a:

Web browser

Each server on a network that needs to act as a web server needs an application layer software package called a (n) ______________.

web server

To get a page from the Web, a user must type in a URL, which stands for:

Uniform Resource Locator

The protocol that makes it possible for a Macintosh web browser to be able to retrieve a Web page from a Microsoft Web server is called the _____________________.

Hypertext Transfer Protocol

There are optional and required parts of an HTTP request.They are:

request line, request header, request body

There are required and optional parts of an HTTP response.They are:

response status, response header, response body

A response status code of 404 means:

the requested page was not found

The acronym, HTML, refers to:

Hypertext Markup Language

Which of the following is not an advantage of instant messaging?

It usually takes days for an IM message to be delivered to the recipient.

The most commonly used e-mail standard is:

Simple Mail Transfer Protocol

In a two-tier client-server architecture, a client computer needs to use an application layer software package called a ________________ to send e-mail:

mail user agent

Another term for a mail user agent is:

e-mail client

IMAP (Internet Message Access Protocol):

permits an e-mail message to remain stored on the mail server even after they have been read by a client computer

In a ___________ architecture, computers are both client and server, thus sharing the work.

Peer-to-peer

The acronym, MIME, refers to:

Multipurpose Internet Mail Extension

What technique is used by most videoconferencing applications to reduce the amount of data being transmitted?

compression

Which of the following is not true about Telnet?

Telnet poses no security threat.

_________ is a special type of one directional; videoconferencing in which content is sent from the server to the user.

webcasting

The software that runs on the mail server is referred to as the____________

Mail transfer agent

The ________________ cloud deployment model provides the highest levels of control, privacy and security.

private

The ________________ clouds realize the benefits from cloud infrastructure (such as speed of deployment) with the added level of privacy and security that private clouds offer.

community

With ______________, the cloud provider manages the hardware including servers, storage, and networking components. The organization is responsible for all the software, including operating system (and virtualization software), database software, and its applications and dat

IaaS

Chapter 3

Data is physically transmitted from one computer or terminal to another in the ________ layer.

physical

____________ refers to the transmission characteristics of the circuit.

logical circuit

In general, networks designed to transmit primarily computer data are likely to be ________.

digital

In general, older networks and local loops designed to transmit voice data are likely to be ________.

analog

Which of the following is not a key advantage of digital transmission?

It permits only low transmission rates.

_________ is the basic physical layout of the circuit.

circuit configuration

A(n) __________ circuit is another name for a multipoint configuration.

shared

Which is not true about point-to-point circuits?

point-to-point circuits reduce the amount of cable required and use the circuit more efficiently than multipoint circuits.

Having a conversation with someone using a cellular phone is an example of _________ transmission.

full-duplex

The ability to transmit in both directions, but only in one direction at a time is an example of _______________ transmission.

half-duplex

The earliest type of fiber optic systems were:

Multimode

___________ refers to the spreading of the signal that different parts of the signal arrive at different times at the destination.

dispersion

_____________ can be thought of as dividing the circuit horizontally.

Frequency division multiplexing

A coding scheme that uses 10 bits to represent each character is capable of representing _________ different characters.

1024

Which of the following statements is correct?

Serial transmission is slower than parallel transmission.

Which type of digital signaling would experience fewer errors because it has more distinct signals?

bipolar

Which of the following is a characteristic of sound waves that can be modulated to convert digital data into analog signals?

phase

If the highest frequency of a circuit is 10KHZ and the lowest frequency is 900 Hz, the bandwidth available for this circuit is :

9100 Hz

The acronym, Modem, stands for _________________.

modulator/demodulator

CH 7


Which of the following is not true about backbone networks?





They tend to use lower speed circuits than LANs.







Which of the following is not a type of hardware device that can be used to interconnect networks?





dumb terminals







Switches:





learn addresses by reading the source and destination addresses







Routers:





may also be called TCP/IP gateways







Which of the following is not a way that a router differs from a switch?





routers can connect two or more networks that use the same data link protocol







Gateways:





can translate one network protocol into another







Which of the following devices is the most complex?





Gateway







Which of the following is a fundamental backbone network architecture?





Virtual LAN







__________ refers to the way in which backbone interconnects the network attached to it and how it manages the way in which packets from one network move though the backbone to other networks.





Backbone architecture







Which of the following is not a technology layer that is considered when designing backbone networks?




decentralized layer







A subnetted or hierarchical backbone can also be called:





Routed backbone







_________ move packets along the backbone based on their network layer address.




Routed backbones







Routers:




require more management than switches







A _____________ type of BN segments (each of which has a special set of subnet addresses that can be managed by different network managers) each part of the network connected to the backbone.




routed backbone







A __________ type of BN has a star topology with one device, such as a switch, at its center.




Switched backbone







Which of the following is not true about switched backbones?




there are many more networking devices in a switched backbone network







Associated with a switched backbone, MDF is an acronym for:




main distribution facility







A _____________ type of BN is a new type of LAN/BN architecture made possible by intelligent, high speed switches that assign computers to LAN segments via software, rather than by hardware.




Virtual LAN







Which of the following is not true about multi-switch VLANs?




All of the above are true statements.







Circuit capacity on a backbone network will not be improved by:




going from 100Base-T Ethernet to 10Base-T Ethernet







Device performance on a backbone network will not be improved by:




translating packets from one protocol to another as they enter the BN







Network demand will not be reduced by:




encouraging the use of applications such as medical imaging







Which of the following would not be part of an ¡°ideal¡± backbone design for the future?




coax cabling throughout LANs and BN







Which of the following can connect two different networks that utilize the same or different data link and network layer protocols as well as the same or different cable type?




Gateway







The backbone architecture layer that is closest to the users is the




Access layer






The _______ is the part of the backbone that connects the LANs together.




Distribution layer







The _________ is the part of the backbone that connects the different backbones together.




Core layer







Devices in a rack are connected together using ___________.




patch cables







Using ______ capabilities, network managers can connect VOIP phones directly into a VLAN switch and configure the switch to reserve sufficient network capacity so that they will always be able to send and receive voice messages.




QoS







Computers can be assigned to a VLAN based on the ________.




physical port on the switch







It appears that the use of _____ is decreasing in backbones while the use of ____ is increasing.




ATM, Ethernet







A(n) _____connects all networks within a company, regardless of whether it crosses state, national, or international boundaries.




enterprise network




Chapter 8




____________ are companies that build a data and telecommunications infrastructure from which other companies can lease services for WANs and MANs.




Common carriers







________ is a type of WAN connection that uses the normal voice telephone network.




T-Carrier services







Which of the following is not a problem with dialed circuits?




Use of these circuits is very simple.







A ___________ is/are devices that permit a user to connect to a digital T-carrier service.




CSU/DSU







Which of the following is not a basic architecture for dedicated circuit networks?




bus







A ________ geometric layout connects all computers in a closed loop, with each computer linked to the next usually with a series of point-to-point dedicated circuits.




ring design







In a ring design WAN,




messages can take a long time to travel from the sender to the receiver







A star architecture:




connects all computers to one central computer that routes messages to the appropriate computer







A star topology is:




dependent upon the capacity of the central computer for its performance







In ______ geometric layout for a network, every computer is connected to every other computer often by point-to-point dedicated circuits.




full mesh design







mesh networks:




require more processing by each computer in the network than in star or ring networks







_____ are dedicated digital circuits that are the most commonly used form of dedicated circuit services in North America today.




T-carrier services







The data rate for a T-1 circuit in North America is:




1.544 Mbps







The data rate for a T-3 circuit in North America is:




44.376 Mbps







SONET:




uses inverse multiplexing above the OC-1 level







Which of the following is not a benefit of packet switched services?




The data transmission rates tend to be lower than dial-up or dedicated circuits.







A _____________ is a user¡¯s connection into a packet switched service.




packet assembly/disassembly device







Which of the following type of networks permit packets from separate messages to be interleaved?




packet switched network







A _______ is a connectionless method of sending data packets on a packet switched service.




datagram







A _________ is a connection-oriented approach to sending packets on a packet switched service.




permanent virtual circuit






______________ are sometimes called private line services.




Dedicated-circuit networks







_____________ is sometimes called a Layer 2.5 technology.




MPLS







Which of the following is a difference between ATM and frame relay?




Frame relay has a maximum CIR speed of up to 45 Mbps.







Ethernet/IP packet networks:




are supported with gigabit fiber optic networks in large cities







A _______________ is a particular type of network that uses circuits that run over the Internet but that appears to the user to be a private network.




virtual private network







Which of the following is a primary advantage of a VPN?




low cost







Which of the following is not a type of VPN?




T-1 VPN







__________ is a term that refers to the speed in converting input packets to output packets.




Latency







Which of the following is not a way to reduce network demand?




moving data further from the applications and people who use them







Which of the following is not a key issue to be considered when selecting a WAN service?




prestige value of using a particular common carrier




Chapter 9




The Internet is one large network.




False







The Internet is flat in structure.




False







As the number of ISPs has grown, a new form of network access point called a metropolitan area exchange has emerged.




True







Peering means that a tier 1 ISP does not charge another tier 1 ISP to transmit its messages.




True







Technologies such as DSL and cable modem are called narrowband technologies.




False







Digital Subscriber Line is a family of multipoint technologies.




False







To use DSL, a customer needs a DSL Access Multiplexer installed at his or her location.




False







The most common type of DSL today is ADSL.




True







In a DSL environment, the line splitter and DSL modem are always two separate devices.




False







At the top of the Internet structure are tier 1 ___________, such as AT&T and Sprint.




Internet service providers







Tier 1 ISPs connect together and exchange data at ___________.




Network Access Points







_________ are smaller versions of NAPs that link a set of tier 2 ISPs.




metropolitan area exchanges







___________ refers to the fact that ISPs do not charge one another (at the same level) for transferring messages they exchange across an NAP or MAE.




Peering







A _________ is the place at which the ISP provides services to its customers.




point-of-presence







A ___________ is used by ISPs to authenticate its customers.




remote-access server







Technologies that provide higher-speed communications than traditional modems (e.g., DSL) are known as ______________ technologies.




broadband







Ddigital _________ Line is a family of point-to-point technologies designed to provide high-speed data transmission over traditional telephone lines.




Subscriber







For access to DSL, __________ equipment is installed at the customer location.




customer premises







A __________ separates traditional voice telephone transmission from the data transmissions in the equipment located at the customer site for DSL.




line splitter







Data traffic from the customers premises is sent to a __________ which is located at the local carrier¡¯s end office.




DSLAM







The _________ is the connection from a home or business to the telephone company end office.




local loop







Most WiMAX providers in the US are using an effective data range of




0.5 to 1.5 miles







A T1 level of ADSL has a maximum downstream rate of about _________ Mbps.




1.5







A(n) __________ is used to connect a fiber optic cable from the cable TV company side to a coaxial cable on the customer side.




optical-electrical converter







Fiber to the Home uses




wavelength division multiplexing







The closest the Internet has to an ¡°owning¡± organization is the ___________.




Internet Society







Which of the following is not part of the work of the Internet Society?




connecting optical-electrical converters







The ________ is a large open international community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and smooth operation of the Internet.




Internet Engineering Task Force







The ___________ is responsible for technical management of IETF and the Internet standards process.




Internet Engineering Steering Group







The _________operates like the IETF through small research groups focused on specific issues.




Internet Research Task Force