Download Fitz and Dennis TB ch05 File

Chapter 5
Network and Transport Layers
True-False Questions
The following are possible True/False questions for tests. The statement is given and the answer
is provided . The level of difficulty (easy, moderate, difficult) and the page number(s) relevant to
the topic are also furnished.
1.
2.
3.
4.
Several different protocols exist that specify how network and/or transport layer packets are
organized.
Answer: True
Difficulty: Easy
TCP/IP is a data link protocol that is used on the Internet.
Reference: p.144
Answer: False
Difficulty: Moderate
Reference: p. 144
The network layer sits between the application layer and the data link layer in the Internet
five-layer network model.
Answer: False
Difficulty: Easy
Reference: p. 144
The network layer is responsible for end-to-end delivery of the message.
5.
Answer: False
Difficulty: Easy
Reference: p. 144
The transport layer routes messages thought the network selecting the best path from the
source to the destination station.
6.
Answer: False
Difficulty: Easy
Reference: p. 144
The network layer depends upon the data link layer for error-free delivery of messages from
one computer to the next.
7.
Answer: True
Difficulty: Easy
Reference: p. 144
The transport layer process running on the destination computer, reassembles the fragmented
application message before passing it up to the application layer
8.
Answer: True
Difficulty: Moderate
Reference: p. 144-145
Software with multiprotocol stacks refers to the fact that the software supports several
different transport/network protocols.
9.
Answer: True
Difficulty: Easy
Reference: p. 145
Some network protocols, such as TCP/IP, are compatible with a variety of different data link
layer protocols, such as Ethernet or frame relay.
Answer: True
Difficulty: Easy
Reference: p. 146
10.
TCP is the network layer protocol used on the Internet today.
11.
Answer: False
Difficulty: Easy
Reference: p. 146
IP is responsible for error-free delivery of packets on a TCP/IP network.
Answer: False
Difficulty: Easy
Reference: p. 146
12.
The TCP portion of TCP/IP performs a data presentation/formatting function.
13.
Answer: False
Difficulty: Easy
Reference: p. 146
The source port identifier in the TCP header tells the TCP software on the destination
computer, which application on the destination it should pass the packet too.
14.
Answer: False
Difficulty: Easy
Reference: p. 147
TCP includes a sequence number so that the packets can be reassembled at the destination in
the correct order.
15.
Answer: True
Difficulty: Moderate
Reference: p. 147
The latest version of IP is IPv7, which increases the address space from 128 bits to 256 bits.
16.
Answer: False
Difficulty: Easy
Reference: p. 147
IPX/SPX is the primary network protocol uses by Microsoft networks.
17.
18.
19.
20.
21.
22.
23.
24.
Answer: False
Difficulty: Easy
Reference: p 148
IPX is the transport layer process and is responsible for the error-free delivery of data on an
IPX/SPX network.
Answer: False
Difficulty: Moderate
X.25 is primarily used in local area networks
Reference: p. 148
Answer: False
Reference: p.148
Difficulty: Moderate
To help determine to which application a transmission should be delivered on a particular
computer, TCP uses the application layer port addresses to distinguish among many open
applications on a computer
Answer: True
Difficulty: Moderate
Reference: p. 149
Source port address is the logical address generated by the application layer on the source
computer to identify the application, which is sending the data.
Answer: True
Difficulty: Easy
The standard port number for Telnet is 53.
Reference: p 149
Answer: True
Difficulty: Easy
Reference: p 150
Because there is a limit on the length of a frame that the data link layer can transmit from
node to node, the transport layer breaks up the message from the application layer into
several smaller packets.
Answer: True
Difficulty: Moderate
Reference: p. 150
Connectionless routing sets up a TCP connection, or virtual circuit between a sender and
receiver.
Answer: False
Difficulty: Moderate
TCP/IP operates only as connection-oriented.
Answer: False
Difficulty: Moderate
Reference:
p. 152
Reference: p. 152
25.
Quality of Service routing is a special type of connection-oriented routing in which different
connections are assigned different priorities.
26.
Answer: True
Difficulty: Easy
An example of an application layer address is www.indiana.edu
27.
Answer: True
Difficulty: Easy
The network layer address for IP is ten bytes long when using IPv4.
28.
29.
Reference: p. 153
Reference:p.153
Answer: False
Difficulty: Easy
Reference: p. 153
The data link layer address is generally encoded in a network card by the card’s
manufacturer.
Answer: True
Difficulty: Easy
Reference: p. 154
IPv4 addresses offer unlimited opportunity for expansion and growth on the Internet.
30.
Answer: False
Difficulty: Easy
Reference: p. 155
Subnet masks tell computers what part of an IP address is to be used to determine whether a
destination is in the same subnet or in a different subnet.
31.
Answer: True
Difficulty: Moderate
Reference: p. 156
Two standards for dynamic addressing for TCP/IP networks are: Bootstrap Protocol and
Dynamic Host Control Protocol.
32.
Answer: True
Difficulty: Easy
Reference: p. 157
Translating an application layer address to a network layer address and finally to a data link
layer address is called address resolution.
33.
Answer: True
Difficulty: Easy
Reference: p.158
Part of the function of address resolution is translating the application layer address of the
destination into a network layer address.
34.
Answer: False
Difficulty: Easy
Reference: p. 158
Domain Name Servers provide the equivalent of directory assistance for application layer
addresses.
35.
Answer: True
Difficulty: Easy
Reference: p. 158
An Address Resolution Protocol message is broadcast to all computers in a subnet to find the
data link layer address.
36.
Answer: True
Difficulty: Moderate
Reference: p. 159-160
Routing is the process of determining the path or route through the network that a particular
message will follow from the sender to the recipient
37.
Answer: True
Difficulty: Easy
Reference: p.161
There are four fundamental approaches to routing: centralized, static routing, dynamic
routing, and monitor routing.
Answer: False
Difficulty: Moderate
Reference: p. 164
38.
When using dynamic routing, routing decisions are always made by a central host or server.
39.
Answer: True
Difficulty: Easy
A hop in a routing calculation is defined as one link or circuit.
40.
Answer: True
Difficulty: Easy
An autonomous system is a network operated by one organization.
41.
Answer: False
Difficulty: Easy
Reference: 165
A routing protocol used inside an autonomous system is called an exterior routing protocol.
42.
43.
Reference: p. 164
Reference: p. 164-165
Answer: False
Difficulty: Easy
Reference: 165
Enhanced Interior Gateway Routing Protocol is a dynamic link state interior routing protocol
developed by Cisco.
Answer: True
Difficulty: Moderate
Reference: 165
A multicast message can be used to send a message to a maximum of two other computers.
Answer: True
Difficulty: Moderate
Reference: 168
MULTIPLE CHOICE
The following are possible multiple-choice questions for tests. The question is posed and the
answer is provided under the choices. The level of difficulty (easy, moderate, difficult) and the
page number(s) relevant to the topic is also furnished.
1.
2.
The ____________ layer links the application layer with the network layer is responsible for
end-to-end delivery of messages.
a. physical
b. transport
c. session
d. presentation
e. data link
Answer: B
Difficulty: Easy
Reference: p. 144
On the destination station, the ________ layer is responsible for providing error-free
messages to the ________ layer.
a. network, data link
b. application, transport
c. data link, network
d. physical, data link
e. transport, application
Answer: B
Difficulty: Moderate
Reference: p. 144
3.
4.
5.
6.
7.
8.
__________ is not an important function of the transport layer.
a. end-to-end delivery of the message
b. taking messages from the application layer
c. routing
d. breaking long messages into smaller packets
e. interfacing with the network layer
Answer: C
Difficulty: Moderate
Reference: p. 144
Network _______ are important to ensure that hardware and software from different vendors
operated by different companies can communicate.
a. protocols
b. directories
c. frequencies
d. topologies
e. directions
Answer: A
Difficulty: Easy
_______ is the dominant network protocol today.
a. SDLC
b. SNA
c. IPX/SPX
d. TCP/IP
e. X.25
Reference: p.145-146
Answer: D
Difficulty: Easy
Reference: p. 146
Transmission Control Protocol/Internet Protocol was developed for ________ in 1974.
a. ARPANET
b. IBM
c. Hewlett-Packard
d. University of Minnesota
e. Xerox
Answer: A
Difficulty: Easy
Reference: p. 146
TCP/IP:
a. is the least commonly used network protocol for LANs because it cannot be
combined with Ethernet
b. performs packetizing, as well as routing and addressing functions
c. is not very efficient and is prone to errors
d. is compatible with only one type of data link protocol, SDLC
e. refers to Telephone Control Procedures/Inter-exchange Procedures
Answer: B
Difficulty: Moderate
Reference: 146
A typical TCP packet has a _______ header of control information.
a. 32-bit
b. 64-bit
c. 160-bit
d. 192-bit
e. 32-byte
Answer: D
Difficulty: Easy
Reference: p. 146
9.
10.
11.
12.
13.
14.
The source destination port identifier tells the destination station _____________.
a. which computer sent the TCP packet.
b. which application layer program that the packet should be sent
c. which application layer process the packet is from.
d. the IP address of the source computer.
e. the IP address of the destination computer.
Answer: C
Difficulty: Moderate
Reference: p.146-147
TCP uses _____________ so that the destination station can reassemble the packets into the
correct order.
a. IP addresses
b. sequence numbers
c. port numbers
d. packet numbers
e. reassembly value
Answer: B
Difficulty: Moderate
Reference: p. 147
The older version of IP has a ________ header of control information.
a. 128-bit
b. 192-bit
c. 1024-bit
d. 160-bit
e. 320-bit
Answer: B
Difficulty: Easy
IP:
a. performs packetizing functions
b. does not have a header
c. is currently in use with only one packet form or structure
d. performs routing functions
e. performs error control functions
Reference: p. 147
Answer: D
Difficulty: Moderate
Reference: p. 147
The newer form of IP, version 6 (Ipv6) is:
a. running out of address space to support the growth of the Internet
b. has a 20 byte header
c. has an increased address size from 32 bits to 128 bits
d. does not include version number in its header
e. does not include hop limit in its header
Answer: C
Difficulty: Moderate
Reference: p. 147
IPX/SPX:
a. refers to Intermodulation Protocol Exchange/Serial Protocol Exchange
b. is the primary network protocol used by Microsoft NT networks
c. is based on a routing protocol developed by IBM in the 1990s
d. is not similar to TCP/IP in function can not be used with Ethernet
e. performs packetizing, as well as addressing and routing functions
Answer: E
Difficulty: Moderate
Reference: p. 148
15.
16.
In the IPX/SPX network model, ______is the network layer protocol and performs the same
routing and addressing functions as its counterpart IP in the TCP/IP model.
a. IPX
b. SPX
c. SAP
d. NCP
e. UDP
Answer: A
Difficulty: Moderate
Reference: p. 148
X.25:
a. does not perform routing functions
b. is a network standard used in wide area networks
c. is extensively used in North America by domestic (non-international) companies
d. is relatively new, therefore it is not used by many organizations
e. has one part that handles addressing and packetizing
Answer: B
17.
18.
19.
Difficulty: Moderate
Reference: p. 148
Assume that more than one application programs that are using the same communications
line on a particular computer. To be able to decide to which application program a message
should be delivered on this computer, TCP/IP relies on the:
a. data link layer address
b. port address
c. application layer address
d. network address
e. IP address
Answer: B
Difficulty: Moderate
Reference: p. 149
The transport layer must break messages from the application layer into several _____ that
can be sent to the data link layer.
a. bits
b. bytes
c. frames
d. packets
e. strings
Answer: D
Difficulty: Easy
Reference: p. 150
The negotiation by the transport layer at the sender with the transport layer at the receiver to
determine what size packets should be set up is done via establishing a(n) ___________
between the sender and receiver.
a. network layer address resolution
b. one way handshake
c. SNA message
d. TCP connection
e. DNS server request
Answer: D
Difficulty: Moderate
Reference: p.150
20.
21.
22.
23.
24.
A virtual circuit is established in the ___________ routing method.
a. asynchronous
b. connection-oriented
c. frequency division
d. application net
e. connectionless
Answer: B
Difficulty: Moderate
Reference: p.152
A special packet called a(n) _____________ packet is sent to the receiver requesting the
establishment of a connection
a. ACK
b. NAK
c. SYN
d. ARQ
e. FIN
Answer: C
Difficulty: Moderate
Reference: p.152
_____________ routing is a method of routing in which each packet makes its own way
through the network.
a. Frequency division
b. Connection-oriented
c. PCMCIA
d. Connectionless
e. Application net
Answer: D
Difficulty: Moderate
Reference: p. 152
In connection-oriented routing, the _________ layer sets up a virtual circuit between the
sender and the receiver.
a. transport
b. network
c. physical
d. data link
e. connection
Answer: A
Difficulty: Moderate
Which of the following is not a protocol used at the application layer.
a. HTTP
b. SMTP
c. FTP
d. Telnet
e. UDP
Answer: E
Difficulty: Moderate
Reference: p. 152
Reference: 152
25.
26.
27.
28.
29.
______________ routing is most commonly used when the application data or message can
fit into one single packet.
a. Frame-oriented
b. Connection-oriented
c. Connectionless
d. Physical-oriented
e. Byte-oriented
Answer: C
Difficulty: Moderate
UDP is not commonly used for:
a. network management control messages
b. RIP messages
c. DHCP addressing messages
d. HTTP requests
e. routing control messages
Reference: p. 152
Answer: D
Difficulty: Moderate
Reference: 152
With QoS routing different __________ are defined, each with different priorities.
a. classes of service
b. domain names
c. application layer addresses
d. data link layer addresses
e. classes of Internet addresses
Answer: A
Difficulty: Easy
An application layer address using TCP/Ipv4 looks like:
a. 128.192.78.5
b. www.cba.uga.edu
c. [email protected]
d. 00-0F-00-81-14-00
e. Building 4, Room 2, User 3
Reference: 153
Answer: B
Difficulty: Moderate
Reference: p.153
A client computer is assigned a data link layer address is by:
a. hardware manufacturers
b. software manufacturers
c. middleware manufacturers
d. network managers who configure a file in a computer’s network layer software
package
e. ISO
Answer: A
Difficulty: Moderate
Reference: p. 154
30.
31.
32.
33.
34.
ICANN:
a. developed the IPX/SPX network layer protocol
b. assigns data link layer addresses
c. approves which network layer addresses (usually, approved or assigned in groups or
classes) can be used by an organization for its computers that will connect to the
Internet
d. developed X.25 network layer protocol
e. refers to Interchange Computer Addressing Networks and Nodes
Answer: C
Difficulty: Moderate
IPv6 will be based upon _________ -byte addresses.
a. 32
b. 24
c. 4
d. 16
e. 8
Reference: p. 155
Answer: D
Difficulty: Moderate
IPv4 uses ________ bytes per Internet address.
a. 4
b. 32
c. 8
d. 24
e. 16
Reference: p. 155
Answer: A
Difficulty: Easy
Reference: p. 155
A(n) ________ refers to a group of computers that are logically grouped together by IP
number.
a. IPv6 group
b. subnet
c. data link group
d. TCP group
e. application net
Answer: B
Difficulty: Moderate
Reference: p. 155-156
A subnet mask of ___________ means that all computers with only the same first two bytes
in their IPv4 addresses are on the same subnet.
a. 11111111.0.0.0
b. 255.255.255.0
c. 255.0.0.0
d. 255.255.0.0
e. 255.255.255.255
Answer: D
Difficulty: Moderate
Reference: p.156
35.
36.
37.
38.
39.
Dynamic addressing:
a. assigns a permanent network layer address to a client computer in a network
b. makes network management more complicated in dial-up networks
c. has only one standard, bootp
d. is always performed for servers only
e. can solve many updating headaches for network managers who have large, growing,
changing networks
Answer: E
Difficulty: Easy
Reference: p. 157
___________ is the translation of application layer addresses into IP addresses.
a. Network interface card reversal
b. IPv6
c. Server name resolution
d. Subnet masking
e. Name service coding
Answer: C
Difficulty: Easy
Server name resolution is done using the:
a. Address Resolution Protocol
b. Border Gateway Protocol
c. Internet Control Message Protocol
d. Routing Information Protocol
e. Domain Name Service
Reference: p. 158
Answer: D
Difficulty: Moderate
Reference: p. 158
When TCP/IP translates an application layer address into an IP address, it sends a special
__________ to the nearest DNS server.
a. broadcast message
b. DNS request packet
c. SNA packet
d. IPX message
e. X.25 packet
Answer: B
Difficulty: Moderate
Reference: 159
When TCP/IP translates a network layer address into a data link layer address, it sends a
special ____________ to all computers in the subnet.
a. physical layer packet
b. multicast message
c. X.25 message
d. broadcast message
e. application layer packet
Answer: D
Difficulty: Easy
Reference: 159
40.
41.
42.
43.
44.
_________ is a specially formatted request used to perform IP address to data link address
resolution.
a. Address Resolution Protocol
b. Domain Service Request
c. HTTP request
d. Link state request
e. Autonomous System Request
Answer: A
Difficulty: Moderate
Reference: 160
___________ is the process of determining the path that a message will travel from sending
computer to receiving computer.
a. Routing
b. Addressing
c. Interfacing
d. Broadcasting
e. Packetizing
Answer: A
Difficulty: Moderate
Reference: p. 161
The _____________ is used by a computer to determine how messages will travel through
the network.
a. routing table
b. configuration listing
c. linking loader
d. bus header assignment list
e. file allocation table
Answer: A
Difficulty: Moderate
Reference: p.161
In its simplest form, the __________ has two columns: the first column lists every computer
and device in the network, while the second column lists the computer or device to which
that computer should send messages, if they are destined for the computer in the first column.
a. linking loader
b. routing table
c. configuration listing
d. bus header assignment list
e. file allocation table
Answer: B
Difficulty: Moderate
The three fundamental approaches to routing are:
a. circuitous, flat, and direct routing
b. connectionless, static, and connection-oriented
c. subordinate, master, and insubordinate routing
d. host, client, and client-server routing
e. centralized, static routing, and dynamic routing
Answer: E
Difficulty: Moderate
Reference: p.161
Reference: p.164
45.
46.
47.
48.
49.
An advantage of centralized routing is:
a. routing does reflect changing network conditions, such as computers that are
overloaded by many messages
b. if anything happens to the computer developing the routing table, the routing tables
cannot be changed until that computer is fixed, or until a new computer is selected to
perform the function
c. routing decisions are simple
d. the routing tables are stored at all computers in the network
e. it requires more processing by each computer or router in the network than dynamic
routing
Answer: C
Difficulty: Moderate
Reference: p.164
With ________ routing, computers or routers count the number of hops along a route and
periodically exchange information on the hop count with their neighbors.
a. circuitous
b. decentralized
c. distance vector
d. indirect
e. link state
Answer: C
Difficulty: Moderate
Reference: p.164
____________ refers to the type of routing in which the routing table is developed by the
network manager and modifications are made only when computers are added to or removed
from the network.
a. Adaptive routing
b. Dynamic routing
c. Static routing
d. Distance vector routing
e. Link state routing
Answer: C
Difficulty: Moderate
_______________ is a type of dynamic routing.
a. Static routing
b. Circuitous routing
c. Centralized routing
d. Link state
e. X.25 routing
Reference: p.164
Answer: D
Difficulty: Easy
Reference: p. 164-165
One drawback to dynamic routing is:
a. Routing usually does not reflect changing network conditions, such as computers
that are overloaded by many messages
b. It cannot be used with non-government networks
c. The transmission of status information “wastes” network capacity that could be used
to send user messages
d. It is the job of the network manager, not the computers or devices themselves, to
maintain the routing table.
e. It requires less processing by each computer than static routing.
Answer: C
Difficulty: Moderate
Reference: p.165
50.
51.
52.
53.
54.
The ping command uses the most basic interior routing protocol on the Internet, which is the:
a. Border Gateway Protocol
b. Internet Control Message Protocol
c. Routing Information Protocol
d. Enhanced Interior Gateway Routing Protocol
e. Open Shortest Path First
Answer: B
Difficulty: Moderate
Reference: p. 166-167
A type of message that is used when sending a message from one computer to another
computer is called a:
a. unicast message
b. multicast message
c. broadcast message
d. guided message
e. radiated message
Answer: A
Difficulty: Easy
Reference: p.168
A special type of message that is used when sending the same message to a specific group of
computers is called a:
a. unicast message
b. multicast message
c. broadcast message
d. guided message
e. radiated message
Answer: B
Difficulty: Easy
Reference: p.168-169
A special type of message that is used when sending the same message to all computers on a
specific LAN or subnet is called a:
a. unicast message
b. multicast message
c. broadcast message
d. guided message
e. radiated message
Answer: C
Difficulty: Easy
IGMP refers to:
a. Internet Giga Memory Parameters
b. Interchange Group Management Parameters
c. Internet Guided Meta Protocol
d. Internet Group Management Protocol
e. Interchange Guided Meta Protocol
Answer: D
Difficulty: Easy
Reference: p.168-169
Reference: p.169
55.
Which of the following is not given to a client computer that is installed on a TCP/IP
network so that it has the appropriate routing/addressing information?
a. application layer address
b. subnet mask
c. its own IP address
d. IP address of its DNS server
e. IP address of a gateway, router, or a switch outside of its subnet
Answer: A
Difficulty: Moderate
Reference: p.169
Short Answer and Essay Questions
1. What does the network layer do? Where does it sit in relationship to the other four
layers of our simplified network model?
2. What are the parts of TCP/IP and what do they do? Who is the primary user of
TCP/IP?
3. What are the parts of X.25 and what do they do? Who is the primary user of
X.25?
4. Compare and contrast the three types of addresses used in a network.
5. What are the different classes of Internet addresses and how are they different?
6. What is a subnet and why do networks need them? What is a subnet mask?
7. How does dynamic addressing work? What benefits and problems does dynamic
addressing provide?
8. What is address resolution? How does TCP/IP perform address resolution for
network layer addresses? How does TCP/IP perform address resolution for data
link layer addresses?
9. What is routing? How does decentralized routing differ from centralized routing?
How does static routing differ from dynamic routing? When would you use static
routing? When would you use dynamic routing? How does static routing differ
from dynamic routing? When would you use static routing? When would you use
dynamic routing?
10. What are the differences between connectionless and connection-oriented
routing? Discuss this in detail and also do a schematic of this. When might UDP
be used? TCP? What is a virtual circuit? What is Quality of Service routing and
why is it useful?
11. Compare and contrast unicast, broadcast, and multicast messages. Explain how
multicasting works.
12. Explain how the client computer in the LAN figure in the book would obtain the
data link layer address of its subnet gateway.
13. Explain how TCP/IP works in a high level way, using a detailed diagram
including the different roles of TCP vs. IP, and the times at which each function is
utilized in the process.
14. List and describe five reasons why TCP/IP has become the predominant protocol
for Internet level transport applications. What do you think is the future market
share potential for proprietary standards? What are some limitations of TCP/IP in
terms of future Internet growth capabilities?
15. What is a routing table? What is the simplest form of a routing table?
16. What is a virtual circuit?
17. Suppose a client computer wants to access a web page on a web server. Assume
that it knows all of the IP addresses and data link layer addresses in the network,
except those for the web server itself. Describe how the client would obtain the IP
address for the web server.
1. Suppose a client computer wants to access a web page on a web server. Assume
that it knows all of the IP addresses and data link layer addresses in the network,
except those for the web server itself. If the web server was on the same subnet as
the client, how would the client obtain the data link layer address for the web
server?
2. Under what conditions does decentralized dynamic routing provide better
performance than decentralized static routing?
3. What is DHCP and why would network managers want to use it?
4. Explain how multicasting works.
5. What four pieces of information does a computer using TCP/IP need in order to
send messages using TCP/IP. Explain why each of these is required.
6. Suppose your manager asks you to discuss how the company’s backbone network
functions in just about four paragraphs to take to senior management. How would
you answer the question? Discuss two or three major points. Your manager
doesn't understand technical terms so be sure to explain any jargon you use.
7. What is the difference between centralized routing and decentralized routing?
What is the difference between static routing and dynamic routing? What is a
distance vector algorithm and what is a link state algorithm? What is interior
routing and what is exterior routing? Define and describe RIP, OSPF, EIGRP,
BGP protocols using these terms. Draw a schematic diagram of routing on the
internet with BGP, OSPF, and RIP.
8. Draw an example of a NAT, including an example of a “realm” with fake IP
addresses, and include the WAN and LAN side source and destination IP’s and
ports in your example. Discuss NAT. What is its purpose? How does the router
know what to do with incoming packets? What does a NAT enabled router look
like to the outside world? What does NAT have to do with IPv6?
9. Be able to convert back and forth between binary and decimal notation for IP
addresses, v4.
10. Draw a schematic of the Domain Name Server process and describe how this
system works and is hierarchically organized. What happens if a URL is not in a
local DNS server?
11. What is ARP and how and why does it work? What is MAC address resolution
and how does it work?