Final Exam - COSC 4325
The _______ is a United States government agency that regulates voice and data communication
FCC
A VLAN requires the computer manager to reconfigure the physical cables to the switch if a computer is moved from one port to another port on a switch .
False
A backbone network that connects many backbone networks spanning several buildings at a single location is often called an Internet backbone .
False
A dedicated circuit is usually not available late at nights or on weekends .
False
A disadvantage of a star architecture is that the failure of one circuit will disrupt the entire network .
False
A hardware device that operates at the application layer is a router .
False
A switch always broadcasts all the packets it receives to all the computers that are connected to the switch .
False
An OC - 1 circuit provides a data rate of 155 Mbps .
False
An access point plays the same role in a wireless network as a router does in a wired Ethernet network .
False
Backbone networks typically use lower speed circuits to interconnect a series of LANS and provide connections to other backbone networks .
False
Cut - through switching has fewer errors than store and forward switching
False
Digital Subscriber Line is a family of multipoint technologies .
False
Fiber optic cable is thicker and heavier than unshielded twisted pair
False
Full mesh design networks are more common than partial mesh design networks
False
One advantage of a routed backbone is that is requires little management.
False
The three latest versions of Ethernet run at speeds of 1Gbps , 10Gbps , and 50 Gbps .
False
A____________ type of BN has a star topology with a switch at its center resulting in all devices on the BN segment being part of the same IP network
Switched backbone
A backbone network is a high - speed network that connects many networks
True
A collision on a bus circuit means that two computers on that circuit have transmitted at the same time .
True
A point of presence is the place at which the ISP provides services to its customers .
True
A room that contains a rack of equipment for a rack - based backbone is also called the main distribution facility ( MDF ) or central distribution facility ( CDF ) .
True
A switch can send and receive on all circuits simultaneously
True
An access point ( AP ) is required to connect a WLAN to a wired network .
True
Directional antennas signals are much stronger than omnidirectional antennas .
True
Hub - based Ethernet is a star physical topology and a bus logical topology .
True
In constructing Wide Area Networks , many organizations do not build their own long distance communication circuits .
True
Peering means that a tier 1 ISP does not charge another tier 1 ISP to transmit its messages .
True
Routers connect two or more network segments that use the same or different data link protocols , but the same network protocol .
True
The Network Interface Card ( NIC ) permits a computer to be physically connected to a network's cable .
True
The RFCs that form the basis for Internet standards are developed by the IETF and its working groups .
True
Virtual private networks permit users to create permanent virtual circuits , or tunnels , through the Internet .
True
When a switch receives an Ethernet frame with a destination address that is not in its forwarding table , the switch will broadcast the frame out all of its other ports .
True
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
A ( n ) _____ is a radio transceiver that plays the same role as a hub or switch in a wired network and connects the WLAN to the wired network .
access point
Which of the following would be least effective in improving backbone performance ?
adding new keyboards to the client computers
A star topology is :
dependent upon the capacity of the central computer for its performance
A _____ is a group of centrally organized , related resources
domain
Which of the following is not a type of hardware device that can be used to interconnect networks ?
dumb terminals
The cheapest time to install network cabling is :
during the construction of the building
In a ring design WAN ,
failure in one circuit means that the network can most likely continue to function
A ( n ) _____ allows many users to share the same set of files on a common , shared disk drive .
file server
When a computer transmits at the same time because it cannot sense that another computer on the WLAN is currently transmitting is referred to as the :
hidden node problem
Of the following , which is not true about fiber optic cable ?
it has a very low capacity
Switches :
learn addresses by reading the source and destination addresses
The _____ is the connection from a home or business to the telephone company end office .
local loop
A logical bus topology
permits every message to be received by every computer on the bus , even when those messages are intended for other computers
Hubs :
usually incorporate repeaters or amplifiers
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
Fiber to the Home uses
wavelength division multiplexing
______ are dedicated digital circuits that are the most commonly used form of dedicated circuit services in North America today .
T-carrier services
Some of the new applications being developed for a high - speed Internet include
Tele - immersion
The most common cable modem standard is Data over Cable Service Interface Specification ( DOCSIS ) .
True
The most common type of DSL today is ADSL .
True
The primary advantage of a routed backbone is that it clearly segments each part of the network connected to the backbone because each segment has its own subnet addresses that can be managed separately
True
The step of understanding current traffic on a network provides a baseline against which future network requirements can be compared.
True
Tier 1 service providers connect together and exchange data at IXPs .
True
Time division multiplexing is more efficient that frequency division multiplexing because the guard-bands used in the frequency division multiplexing or not needed.
True
Today, many organizations design networks using the building - block approach.
True
Token passing is a term that refers to hub polling, in which one computers starts a poll and passes it to the next computer on a multipoint circuit.
True
WDM is a version of FDM used in fiber-optic cables.
True
Your typical web browsing scenario where a person using a web browser accesses a web page from a server on the Internet is a good example of a client - server application architecture.
True
A backbone network is:
a high speed central network that connects other networks in a distance spanning up to several miles.
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
Errors on a network can occur:
because of noise on the line
The goal of the needs analysis step is to produce a _______ or a statement of the network elements necessary to meet the needs of the organization.
logical network design
Routers :
may also be called TCP / IP gateways
In a ring design WAN ,
messages can take a long time to travel from the sender to the receiver
The building block design approach is sometimes called:
narrow and deep
The ________ layer is responsible for routing of messages from the sender to the final destination.
network layer
Cross talk:
occurs when one circuit picks up signals in another
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
A ____ is a user's connection into a packet switched service .
packet assembly / disassembly device
With contention:
computers wait until the circuit is free before they send data
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
A "thick client" architecture approach:
places all or almost all of the application logic on the client
________ is the presentation of information to the user and the acceptance of the user's commands.
presentation logic
The traditional network design approach does not work well for ______ networks.
rapidly growing
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
In the Internet model, the application layer corresponds to the layer(s) of the OSI model.
session, presentation, and application
Which of the following is not included in the key deliverable for the needs assessment stage of the building-block network design process , the set of logical network diagrams?
specific routers that have been chosen to implement the proposed network
We transmit 1000 bytes using Ethemet 802.3ac frame (see Figure 4-8a). Assume VLAN tag is not used and the control field is 1 byte long . Ignore Interframe spacing. What is the transmission efficiency? Round your answer to the nearest whole number percentage.
97
Give the answer in milliseconds. My office has a 1 Gbps connection to the Internet. How long does it take for my office to upload the 100 files in the previous question. (remember, 1 ms = one thousandth of a second)
160
How many bits are uploaded each day from my office? Give the answer in megabits. My office uploads 100 files each day where the average size of a file is 200,000 bytes (remember, 1 megabit = 1 million bits).
160
What is the bit rate of an analog circuit with a 20 MHz symbol rate using 256 - QAM ? Give the answer in Mbps.
160
Asynchronous transmission uses 7 bits for transmitting a character and 1 start bit and 1 parity bit for each character. What is the transmission efficiency in % (rounded to the nearest whole number) ?
78
A ______ is a device that permits a customer to connect to a digital T - carrier service
CSU / DSU
______ refers to the amount of data transmitted on a circuit.
Circuit loading
_____ are companies that build a data and telecommunications infrastructure from which other companies can lease services for WANs and MANS .
Common carriers
An intranet VPN connects different organizations over the Internet .
False
Contention MAC approaches work better in a large network with high usage.
False
Data transmission errors are typically uniformly distributed in time
False
Digital transmission produces more errors than analog transmission.
False
Due to advances in high speed communication networks , the information lag, or the time it takes for information to be disseminated around the world, has been significantly lengthened.
False
Ethernet is a layer 3 protocol , which operates at the network layer .
False
Ethernet is an example of a network layer protocol.
False
Fiber optic cable carries signals in traditional electrical form.
False
Frequency modulation refers to the changing of the height of the sound wave.
False
Guided media refers to the type of media in which the message is broadcast through the air.
False
Host-based and client-based networks are similar in that the client computer performs most of the work.
False
In simplex transmission, the data flows in both directions at the same time
False
Layer - 3 switches switch messages based only on their data link layer address .
False
MPLS operate at layer 4 .
False
Needs analysis is the final step in the building block approach to network design.
False
Nonreturn to zero is a type of unipolar signaling
False
Only the sender of a data transmission needs to be concerned about the rules or protocols that govern how It communicates with the receiver
False
Propagation delay is negligible with satellite transmission.
False
Routers can only connect the same type of cable .
False
Symbol rate is the number of bits transmitted per second.
False
Technologies such as DSL and cable modem are called narrowband technologies .
False
The Internet is flat in structure .
False
The Internet is one large network .
False
The OSI model is currently the most widely implemented network model used to develop and build networks of any size, including the Internet itself.
False
The Simple Mail Transfer Protocol is the least commonly used e-mail standard
False
The application layer is the seventh layer of the Internet model and specifies the type of connection and the electrical signals that pass through it.
False
The campus backbone (or core layer) is the network architecture component responsible for providing end user access to the network.
False
The goals in the needs analysis step of network design are exactly the same when designing LANs vs. when designing WANS.
False
The standard protocol for communication between a Web browser and a Web server is the web protocol.
False
The traditional network design approach works very well for rapidly changing networks.
False
The turnpike effect results when a network is used at a much lower rate than was anticipated when it was designed.
False
Today, all network traffic is due to traffic from internal application systems.
False
Today, the most expensive part of the network is the hardware.
False
Using the POP standard for client to server e-mail communication, the e-mail messages remain on the server computer.
False
When obtaining the support of senior management for a proposed network it is important to use as much technical network jargon as possible.
False
With modem communications, the receiving modem converts the incoming digital signal from the telephone line into an analog signal that can be understood by the computer.
False
A T1 circuit provides a data rate of 1.544Mbps
True
A WAN with a ring topology can use full or half duplex circuits .
True
A car manufacturer may give access to certain portions of its network to some of its suppliers via the Internet. This is an example of an extranet.
True
A traditional network design approach follows a structured systems analysis and design process similar to that used in building applications.
True
A walkie-talkie is an example of half-duplex transmission.
True
ADSL uses FDM to create three channels over the one local loop circuit : one for voice , one for upstream data , and one for downstream data .
True
At the transport layer in the Internet model , TCP is responsible for breaking large files received from the application layer into smaller messages and opening a connection to a server for transferring them.
True
Attenuation refers to the loss of signal strength.
True
Coding schemes are groups of bits that translate into the "alphabet" of any given system.
True
Contention is commonly used with Ethernet local area networks
True
Cost assessment is used to look at the relative cost of technologies used in a network design.
True
Data communication standards enable each layer in the sending computer to communicate with its corresponding layer in the receiving computer.
True
Data compression can increase the throughput of a communication link.
True
Ethernet, a common LAN technology, uses Manchester encoding.
True
If a computer transmits a message containing "ABC" and the destination computer receives "abc" as the message, the message is corrupted
True
In a client-server network, the presentation logic is the responsibility of the client computer.
True
In full-duplex transmission, two stations can send and receive simultaneously.
True
Switches and routers are devices that can connect networks to the BN .
True
The campus backbone is usually faster than the backbones used inside buildings.
True
The data link layer accepts messages from the network layer and controls the hardware that transmits them.
True
The four general functions of any application program are: data storage, data access logic, application logic and presentation logic.
True
With odd parity and a 7 - bit ASCII code, 0110011, what is the parity bit ?
1
Consider case study IV (Alpha Corp on page 110). How many bits per second are generated by web accesses. Give your answer in whole number kbps.
267
Consider case study IV (Alpha Corp) on page 110. How many bits per second are generated by both email and web applications? Give your answer in whole number kbps.
270
Which of the following is not a step under the traditional network design approach?
An analyst takes the traffic on the current network and then multiplies that by a factor of 3.65 to come up with the estimate of the total traffic for the new network
Data communications and networking can be considered as a global area of study because:
Both A&B. A. new technologies and applications emerge from a variety of countries and spread around the world B. the technologies enable global communication
In a _____ more than one data bit is changed by the error-causing condition .
Burst error
Which of the following would not be a type of circuit that needs to be considered when planning for technology design capacity?
Ethernet
A(n) is a LAN that uses the same technologies as the Internet but is provided to invited users outside the organization who access it over the Internet.
Extranet
A "thin client" approach places most of the application logic on the client.
False
A VLAN network assigns computers to LAN segments by hardware .
False
A local area network (LAN) connects other LANs and backbone networks (BNS) located in different areas to each other and to wide area networks in a span from 3 to 30 miles.
False
Which department of Next Day Air Service Inc (the case study) has no automation whatsoever?
Fleet Maintenance Division
Which of the following is a term used to group together the physical and data link layers?
Hardware layers.
Which of the following new Internet efforts was started by 34 universities ?
Internet2
A(n) is a LAN that uses the same technologies as the Internet but is open to only those inside the organization
Intranet
Which of the following is not a key advantage of digital transmission?
It permits only low transmission rates.
Which of the following is not directly contributing to the dramatic increase in network traffic today?
Much of the video processing on computers can be off - loaded from the CPU onto high end video cards .
In the _______ step of the building-block process to network design , the network designer examines the available technologies and assesses which options will meet the users' needs.
Needs analysis
______ is an effective way to prevent Impulse noise cross talk, and Intermodulation noise.
Shielding wires
In the three-tier architecture, the software on the client computer is responsible for the presentation logic, an application server is responsible for the application logic and a separate database server is responsible for the data access logic and data storage.
True
Microwave transmissions require a line of sight between any two points.
True
Middleware is a software that can translate between software from different vendors.
True
Networks requirements can be divided into mandatory, desirable and wish-list requirements.
True
Scalability refers to the ability to increase or decrease the capacity of the computing infrastructure in response to changing capacity needs.
True
Which of the following is false about staff costs for a network?
When a variety of devices from different vendors are used in a network , it takes less time to perform network management activities
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 such as a set of rooms, a single building, or a set of well-connected buildings
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, only the server is responsible for the ____ logic .
data access
Two fundamentally different types of data are:
digital and analog
When a signal is reflected back to the transmitting equipment, it is called a(n)
echo
The primary reason for networking standards is to:
ensure that hardware and software produced by different vendors can work together
Which of the following media is least susceptible to noise ?
fiber optic cable
Which of the following is not one of the three major steps used in the building-block process to network design?
implementation and maintenance
Media access control
is not very important in point to-point with full duplex configuration
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
One underlying problem with a host-based network is that:
the server can get overloaded since it must process all messages
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
The _________ layer performs error checking which is redundant to some extent with the function of the _________ layer.
transport, data link
Mesh networks :
typically contain more circuits in the network than in star or ring networks
For access to DSL , ______ equipment is installed at the customer location .
customer premises
A T1 level of ADSL has a maximum downstream rate of about _______ Mbps .
1.5
Data traffic from the DSL customer premises is sent to a which is located at the local carrier's end office.
DSLAM
In general , tier 3 ISPs make money by charging
customers
Ethernet LAN was developed by
DEC , Xerox , and Intel
The _____ is responsible for technical management of IETF and the Internet standards process .
Internet Engineering Steering Committee
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
At the top of the Internet structure are tier 1 ______ such as AT & T and Sprint .
Internet service providers
_______ is a common standard for use by layer 2 access VPNs for encapsulation .
L2TP
A subnetted or hierarchical backbone can also be called :
Routed backbone
_____ is the software that controls the network .
Network Operating System
Which of the following is not a basic LAN component ?
PAD
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 .
Which of the following is true regarding switched backbones ?
They place all network devices for one part of the building physically in the same room , often in a rack of equipment
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 technology layer that is considered when designing backbone networks ?
decentralized layer
Technologies that provide higher - speed communications than traditional modems e.g. , DSL are known as technologies .
broadband
Which of the following is not a basic architecture for dedicated circuit networks ?
bus
A ( n ) ______ contains a series of cable modems / multiplexers and converts the data from cable modem protocols into protocols needed for Internet traffic , before passing them to a router connected to an ISP POP .
cable modem termination system
A ( n ) _____ is not a common type of dedicated server
collision server
Routers :
connect different IP networks or subnetworks
A star architecture :
connects all computers to one central computer that routes messages to the appropriate computer
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
Which of the following is not true about switched backbones ?
there are many more networking devices in a switched backbone network compared to the number of LANS attaching to it
