Which of the following describe how TCP adds reliability
to communication? (Choose three.)
Hosts using TCP set up virtual circuits at the beginning
of the transmission using the three-way handshake.
Hosts using TCP set the error-checking frequency at the
beginning of the transmission and maintain this frequency for the duration
of the data transfer.
When a sending host does not receive an acknowledgment
within a timed interval it retransmits data.
The receiving host acknowledges that it has received the
expected number of segments and requests additional data.
The receiving host acknowledges any incorrectly received
data and requests retransmission of damaged or missing bytes.
The sending host transmits each segment twice to ensure
that data is not lost.
2
A computer programmer is developing software that
requires a reliable stream of data. Which protocol can be used in the
software design to eliminate the need for building error detection and
recovery into the application program?
TCP
IP
ICMP
UDP
HTTP
3
Why is TCP considered a connection-oriented protocol?
It establishes a virtual connection between hosts using
a two-way handshake.
It uses IP to guarantee delivery of packets between
hosts.
It requires hosts to go through a synchronization
process prior to data transmission.
It creates a connection that depends on application
layer protocols for error detection.
4
At which point in the transmission process are segments
numbered?
when received
when reassembling
before transmission
while negotiating window size
5
What is dynamically assigned by the source host when
forwarding data?
destination IP address
destination port number
default gateway address
source IP address
source port number
6
How are originating source port numbers assigned during
the data encapsulation process?
assigned manually by the user when starting the
application
assigned dynamically by the source host
assigned by the routing protocol during the lookup
process
assigned by the destination host during session
negotiation
7
Which of the following would an administrator do to
defend against a denial of service SYN flooding attack? (Choose two.)
Hide the source of incoming IP addresses.
Decrease the connection timeout period.
Synchronize all host communication.
Increase the connection queue size.
Flood the network with false SYN requests.
8
When a host receives a data segment, what allows the
host to determine which application should receive the segment?
IP source address
IP destination address
PAR
sliding window
port number
SYN packet
9
What is used by UDP to determine if the data or header
has been transferred without corruption?
lower layer protocols
checksum
PAR
sliding window
acknowledgment and retransmission
IP
10
What is the purpose of using port numbers in the
transport layer?
to identify the segment as being either TCP or UDP
to provide reliability during data transport
to identify the interface port number used by the router
when forwarding data
to track multiple conversations that occur between hosts
11
In the TCP header, which of the following determines the
amount of data that can be sent before receiving an acknowledgment?
segment number
priority number
window size
value in the length field
value in the port field
acknowledgment number
12
What does TCP use to ensure reliable delivery of data
segments?
upper layer protocols
lower layer protocols
sequence numbers
port numbers
13
Which of the following protocols uses UDP for transport
layer services?
SMTP
HTTP
DNS
FTP
14
What type of segment and data is shown in the graphic?
a UDP segment carrying e-mail traffic
a TCP segment carrying FTP traffic
an IP segment carrying FTP traffic
a UDP segment carrying web traffic
a TCP segment carrying web traffic
an IP segment carrying e-mail traffic
15
What is the purpose of Positive Acknowledgment and
Retransmission (PAR)?
PAR allows the presentation layer to request that data
be resent in a format the destination host can process.
PAR provides a mechanism for the receiving device to
request that all segments be retransmitted if one segment is corrupt.
PAR helps ensure that a number of data segments sent by
one host are received by another host before additional data segments are
sent.
PAR is used to renegotiate the window size during the
synchronization process.
16
Which of the following are functions of the TCP
protocol? (Choose three.)
translation of data
synchronization
path determination
flow control
data representation
reliability
17
What is used by both TCP and UDP when creating a
segment?
IP address
MAC address
IPX address
socket or port number
acknowledgment number
sequence number
18
Which authority has control over the assignment of port
numbers for applications?
IEEE
IANA
InterNIC
Software Developers Association
19
Which of the following describe types of port numbers
that can be represented in the headers of TCP and UDP segments? (Choose
three.)
connectionless
well-known
operational
dynamic
registered
static
20
What is the purpose of the three-way handshake that
occurs between hosts using TCP as the transport layer protocol?
to increase the number of packets that can be sent
before an acknowledgment is required
to allow a host to forward data to a router
to establish a round trip connection between sender and
receiver before data is transferred
to provide a mechanism for data encryption and
compression
21
During the encapsulation process, in which order are the
IP address, MAC address, and port number assigned when the router is
establishing communication with the TFTP server?
IP address, MAC address, port number
MAC address, IP address, port number
port number, IP address, MAC address
port number, MAC address, IP address
22
Which of the following describes a type of denial of
service attack designed to exploit the normal function of the TCP three-way
handshake?
A host sends a packet with a spoofed source IP address.
A host sends a packet with an incorrect destination IP
address.
A source sends a packet containing a garbled header.
A host sends an oversized packet that fills the memory
buffers of the destination host.
A host sends a packet that contains a virus.
A host sends a packet that contains a worm.
23
Which transport layer unit of information places the
port number in the header?
