Cisco Q3 Mod 8 & 14 Flashcards
1
Q
Provides services to allow end devices to exchange data across networks.
A
The network layer, or OSI Layer 3
2
Q
End devices must be configured with a unique IP address for identification on the network.
A
Addressing end devices
3
Q
The network layer ENCAPSULATES the protocol data unit (PDU) from the transport layer into a packet.
A
Encapsulation
4
Q
The network layer provides services to direct the packets to a DESTINATION host on another network.
A
Routing
5
Q
When the packet arrives at the network layer of the destination host, the host CHECKS the IP header of the packet.
A
De-encapsulation
6
Q
__ ____________ the transport layer (the layer just above the network layer) segment or other data by adding an IP header. The IP header is used to deliver the packet to the destination host.
A
IP Encapsulation
7
Q
There is no CONNECTION with the destination established before sending data packets.
A
CONNECTIONLESS
8
Q
IP is inherently unreliable because packet delivery is NOT guaranteed.
A
Best Effort
9
Q
Operation is independent of the medium (i.e., copper, fiber-optic, or wireless) carrying the data.
A
Media Independent
10
Q
(T) IP is connectionless, meaning that no dedicated end-to-end connection is created by IP before data is sent.
A
CONNECTIONLESS
11
Q
(T) IP also DOES NOT require additional fields in the header to maintain an established connection.
A
Best Effort
12
Q
(T) UNRELIABLE means that IP does not have the capability to manage and recover from undelivered or corrupt packets.
A
Media Independent
13
Q
Which OSI layer SENDS segments to be encapsulated in an IPv4 or IPv6 packet?
A
Transport layer
14
Q
Which layer is responsible for taking an IP packet and preparing it for TRANSMISSION over the communications medium?
A
Data Link Layer
15
Q
What is the term for SPLITTING up an IP packet when forwarding it from one medium to another medium with a smaller MTU?
A
FRAGMENTATION
16
Q
Which delivery method does not guarantee that the packet will be delivered fully without ERRORS?
A
Best Effort
17
Q
Contains a 4 - bit binary value set to 0100 that identifies this as an IPv4 packet
A
Version
18
Q
FORMERLY called the type of service (ToS)
A
DiffServ
19
Q
Contains an 8 bit binary value that is used to limit the LIFETIME of a packet.
A
Time To Live (TTL)
20
Q
This field is used to identify the next level PROTOCOL
A
Protocol
21
Q
This is used to DETECT corruption in the IPv4 header
A
Header Checksum
22
Q
This contains a 32 bit binary value that represents the SOURCE IPv4 address of the packet
A
Source IPv4 Address
23
Q
This contains a 32 bit binary value the represents the DESTINATION IPv4 address of the packet
A
Destination IPv4 Address
24
Q
IHL
A
The Internet Header Length
25
What are the two most commonly referenced fields in an IPv4 packet header that indicate where the packet is coming from and where it is going? (Choose two.)
Destination IP address
Source IP address
26
Which statement is correct about IPv4 packet header fields?
The source and destination IPv4 addresses remain the same while travelling from source to destination
27
Which field includes common values such as ICMP (1), TCP (6), and UDP (17)?
Protocol
28
IPv4 has a LIMITED number of unique public addresses available.
IPv4 address depletion
29
Network Address Translation (NAT) is a technology commonly implemented within IPv4 networks.
Lack of end-to-end connectivity
30
While NAT has extended the lifespan of IPv4 it was only meant as a transition mechanism to IPv6.
Increased network complexity
31
IPv6 addresses are based on 128-bit hierarchical addressing as opposed to IPv4 with 32 bits.
Increased address space
32
The IPv6 header has been simplified with fewer fields.
Improved packet handling
33
With such a large number of public IPv6 addresses, NAT between a private IPv4 address and a public IPv4 is not needed.
Eliminates the need for NAT
34
Which three options are major issues associated with IPv4? (Choose three.)
IP address depletion
Increased network complexity and Internet routing table expansion
Lack of end to end connectivity
35
Which two options are improvements provided by IPv6 as compared to IPv4? (Choose two.)
INcreased the IP address space
uses a simpler header to provide improved packet handling
36
Which is true of the IPv6 header?
It consists of 40 octets
It contains 8 header fields
37
Which is true of the IPv6 packet header?
The hop limit field replaces the IPv4 Time to Live field
38
A host can **PING** itself by sending a packet to a special IPv4 address of 127.0.0.1 or an IPv6 address ::1, which is referred to as the loopback interface.
Ping
39
****This is a destination host that is on the same **local** network as the sending host.
LOCAL host
40
This is a destination host on a **remote** network.
Remote Host
41
Which statement about host forwarding decisions is true?
Local Hosts can reach each other without the need of a router
42
Which default gateway statement is true?
The default gateway address is the IP address of the router on the local network
43
Which two commands could be entered on a Windows host to view its IPv4 and IPv6 routing table? (Choose two.)
netstart -r
route print
44
What is the command used on a Cisco IOS router to view the **routing** **table**?
Show IP ROUTE
45
What does a code of “O” indicate next to a route in the routing table?
A route learned dunamically from OSPF
46
This type of route is also known as a gateway of last resort.
This route is used to forward traffic to a specific direction when there is not a match in the routing table
Default Route
47
Which is a characteristic of static routes?
They are manually configured
48
True or False? A router can be configured with a combination of both static routes and a dynamic routing protocol.
T
49
Which field in an IPv6 packet is used by the router to determine if a packet has expired and should be dropped?
Hop Limit
50
Which field in an IPv4 packet header will typically stay the same during its **transmission**?
Destination ADdress
51
Which information is used by routers to forward a data packet toward its **destination**?
Destination IP address
52
What was the reason for the creation and implementation of IPv6?
To relieve IPv4 address depletion
53
Which IPv4 address can a host use to ping the loopback interface?
127.0.0.1
54
A computer has to send a packet to a destination host in the same LAN. How will the packet be sent?
A packet will be sent directly to the destination host
55
(T) Application layer programs generate data that must be exchanged between source and destination hosts
56
At the transport layer, each set of data flowing between a source application and a destination application is known as a conversation and is tracked separately. It is the responsibility of the transport layer to maintain and **track** these multiple conversations.
Tracking Individual Conversations
57
IP is concerned only with the structure, addressing, and routing of packets. IP does not specify how the delivery or **transportation** of the packets takes place.
Transport Layer Protocols
58
IP is concerned only with the structure, addressing, and routing of packets, from original sender to final destination. IP is not responsible for guaranteeing delivery or determining whether a connection between the sender and receiver needs to be established.
Transmission Control Protocol
59
is a simpler transport layer protocol than TCP.
User Datagram Protocol (UDP)
60
Which layer is responsible for establishing a **temporary** communication session between the source and destination host applications?
Transport Layer
61
Which three are transport layer responsibilities? (Choose three.)
Conversation Multiplexing
Segmenting data and resembling segments
Tracking individual conversation
62
Which transport layer protocol statement is true?
UDP Is a best effort delivery protocol
63
Which transport layer protocol would be used for VoIP applications?
User Datagram Protocols UDP
64
TCP is a connection-oriented protocol that negotiates and **establishes a permanent connection (or session)** between source and destination devices prior to forwarding any traffic.
Establishes a Session
65
For many reasons, it is possible for a segment to become corrupted or lost completely, as it is transmitted over the network.
Ensures Reliable Delivery
66
Because networks may provide multiple routes that can have different transmission rates, data can arrive in the wrong **order**.
Provides Same-Order Delivery
67
Network hosts have limited resources (i.e., memory and processing power). When TCP is aware that these resources are overtaxed, it can request that the sending application reduce the rate of data flow.
Supports Flow Control
68
is a stateful protocol which means it keeps track of the state of the communication session. To track the state of a session, **TCP** records which information it has sent and which information has been acknowledged.
TCP Header
69
Which transport layer protocol ensures reliable same-order delivery?
TCP
70
Which TCP header statement is true?
It consists of 10 fields in a 20 byte header
71
Which two applications would use the TCP transport layer protocol? (Choose two.)
FTP
HTTP
72
These applications can tolerate some data loss, but require little or no delay. Examples include VoIP and** live** streaming **video**.
Live video and multimedia applications
73
Source Port
A 16-bit field used to identify the source application by port number.
74
Destination Port
A 16-bit field used to identify the destination application by port number.
75
Length
A 16-bit field that indicates the length of the UDP datagram header.
76
Checksum
A 16-bit field used for error checking of the datagram header and data.
77
These applications can tolerate some data loss, but require little or no delay. Examples include VoIP and **live** streaming video.
Live video and multimedia applications
78
Applications with simple transactions where a host sends a request and may or may not receive a reply. Examples include DNS and DHCP.
Simple request and reply applications
79
Unidirectional communications where flow control, error detection, acknowledgments, and error recovery is not required, or can be handled by the application.
Applications that handle reliability themselves
80
Which of the following is a stateless best-effort delivery transport layer protocol?
UDP
81
Which UDP header statement is true?
It consists 4 fields in an 8 byte header
82
Which two applications would use the UDP transport layer protocol? (Choose two.)
TFTP
VolP
83
Which two fields are the same in a TCP and UDP header? (Choose two.)
Destination port number
Source port number
84
Assume a host with IP address 10.1.1.10 wants to request web services from a server at 10.1.1.254. Which of the following would display the correct socket pair?
10.1.1.10:1099, 10.1.1.254:80
85
Which port group includes **port** numbers for FTP, HTTP, and TFTP applications?
Well-known ports
86
Which Windows command would display the protocols in use, the local address and port numbers, the foreign address and port numbers, and the connection state?
netstat
87
U.R.G
Urgent pointer field significant
88
A.C.K
Acknowledgment flag used in connection establishment and session termination
89
P.S.H
Push function
90
R.S.T
Reset the connection when an error or timeout occurs
91
S.Y.N
Synchronize sequence numbers used in connection establishment
92
F.I.N
No more data from sender and used in session termination
93
Which of the following would be valid source and destination ports for a host connecting to an email server?
Source: 49152, Destination: 25
94
Which control bit flags are used during the three-way handshake?
SYN and ACK
95
How many exchanges are needed to end both sessions between **two** hosts?
Four exchanges
96
What field is used by the destination host to reassemble segments into the original order?
Sequence Number
97
What field is used to provide flow control?
Window Size
98
What happens when a sending host senses there is congestion?
The sending host reduces the number of bytes it sends before receiving an acknowledgement from the destination host.
99
Why is UDP desirable for protocols that make a simple request and reply transactions?
Low overhead
100
Which UDP datagram reassembly statement is true?
UDP reassembles the data in the order that it was received
101
Which of the following would be valid source and destination ports for a host connecting to a DNS server?
Source 49152, Destination:53
102
The transport layer is the link between the application layer and the lower layers that are responsible for network transmission.
Transportation of Data
103
TCP establishes sessions, ensures reliability, provides same-order delivery, and supports flow control.
TCP Overview
104
UDP reconstructs data in the order it is received, lost segments are not resent, no session establishment, and UPD does not inform the sender of resource availability.
UPD Overview
105
The TCP and UDP transport layer protocols use port numbers to manage multiple simultaneous conversations
Port Numbers
106
Each application process running on a server is configured to use a port number.
TCP Communications Process
107
For the original message to be understood by the recipient, all the data must be received and the data in these segments must be reassembled into the original order.
Reliability and Flow Control
108
UDP is a simple protocol that provides the basic transport layer functions.
UPD Communication
109
Which transport layer feature is used to establish a connection-oriented session?
TCP 3 way shake
110
What is the complete range of TCP and UDP well-known ports?
0 to 1023
111
What is a socket?
The combination of a source ip address and port number or a destination IP address and port number
112
How does a networked server manage requests from multiple clients for different services?
Each request has a combination of source and destination port numbers, coming from a unique IP address
113
What happens if part of an FTP message is not delivered to the destination?
The part of the FTP message that was lost is re-sent
114
What type of applications are best suited for using UDP?
Applications that are sensitive to delay
115
Network congestion has resulted in the source learning of the loss of TCP segments that were sent to the destination. What is one way that the TCP protocol addresses this?
The source decreases the amount of data that it transmits before it receives an acknowledgement from the destination
116
Which two operations are provided by TCP but not by UDP? (Choose two.)
retransmitting any unacknowledged data
acknowledging received data
117
What is the purpose of using a source port number in a TCP communication?
to keep track of multiple conversation between devices
118
Which two flags in the TCP header are used in a TCP three-way handshake to establish connectivity between two network devices? (Choose two.)
SYN, ACK
119
What TCP mechanism is used to enhance performance by allowing a device to continuously send a steady stream of segments as long as the device is also receiving necessary acknowledgements?
Sliding window
120
Which action is performed by a client when establishing communication with a server via the use of UDP at the transport layer?
The client randomly selects a source port number
121
Which two services or protocols use the preferred UDP protocol for fast transmission and low overhead? (Choose two)
Volp
DNS
122
Which number or set of numbers represents a socket?
192.168.1.1:80
123
What is a responsibility of transport layer protocols?
tracking individual conversations
124
Select the statement that incorrectly describes IP
The destination will receive the packet when it arrives.
125
The field in the IPv4 header that indicates the life of the packet.
TTL
126
It is the information that routers utilize to direct a data packet to its **intended location.**
Destination IP address
127
What routing table entry has a next hop address associated with a destination network?
remote routes
128
This process divides the packet into smaller units.
Segmentation
129
The basic characterisitic of the IP protocol
connectionless
130
A router recieves a packet from fastethernet 0/1 interface and was able to determined that the packet needs to be forwarded **out of Serial 0/0/0 interface.** What will the router do next?
route the packet out the serial 0/0/0
131
Which of the following statements for IP encapsulation is true?
The impact on layer 4 segment varies depending on whether IPv4 or IPv6 is used for IP encapsulation.
132
What IPv4 header field identifies the upper layer **protocol** carried in the packet?
Protocol
133
****What information is provided by the **loopback** **test**?
Loopback test
134
Sending a packet to a destination host outside the local area network. The packet will be sent in
what way?
The packet will be sent to the default gateway first, an then, depending on the response from the gateway, it
may be sent to the destination host.
135
Sending a packet to a destination host inside the same LAN. The packet will be sent in what way?
The packet will be sent to the default gateway first, an then, depending on the response from the gateway, it
may be sent to the destination host.
136
IP is a connectionless protocol, which means
It does not concern itself with the type of frame required or the media type.
137
Which is NOT a limitation of IPv4?
Lack of end-to-end connectivity
138
The IPv6 equivalent of the IPv4 address 127.0.0.1
::1
139
Which of the following is not a function of the network layer?
Application to application communication
140
As long as the interface is operational and has an address, the router will automatically add these
type of routes
Static
141
What is one advantage that the IPv6 **simplified** header offers over IPv4
efficient packet handling
142
****The field in the IPv4 to **detect** **corruption** in the packet header
Checksum
143
This route is used to forward traffic to a specific direction when there is not a match in the routing
table
Default Route
144
Select the statement that incorrectly describes IP
The destination will receive the packet when it arrives.
145
What routing table entry has a next hop address associated with a destination network?
remote routes
146
The basic characterisitic of the IP protocol
Connectionless
147
********A router recieves a packet from fastethernet 0/1 interface and was able to determined that the
packet needs to be forwarded **out o**f **Serial** **0/0/0 interface**. What will the router do next?
route the packet out the serial 0/0/0
