CCNA 1 - Module 4 Exam Answers


What is the purpose of the TCP three-way handshake?

to adjust the size of the sliding window

to establish the presence of the destination host

to confirm the availability of the destination port

to synchronize sequence numbers prior to data transmission


What are the features of the User Datagram Protocol (UDP). (Choose three.)

no guaranteed delivery of datagrams


provides reliable full-duplex data transmission

reliability provided by the application layer


utilizes sliding windowing techniques


Which protocol is used by FTP to transfer files over the Internet?






How does windowing ensure that a data packet will be delivered to the recipient in the same order, undamaged, and reliably? (Choose two.)


collision avoidance

window size adjustment

dynamic packet size adjustment

encapsulation packet size


The network administrator for ABC company needs to send large amounts of information to many destinations at one time and does not need any verification that the data has been received. Which transport protocol would the administrator use?








Based on the transport layer header shown in the diagram, which of the following statements describe the established session? (Choose two.)

This is a UDP header.

This contains a Telnet request.

This contains a TFTP data transfer.

The return packet from this remote host will have an Acknowledgement Number of 43693.

This is a TCP header.


Which of the following best describe the transport layer three-way handshake? (Choose two.)

TCP is established by using the three-way handshake to synchronize sequence numbers.

UDP is established by using the three-way handshake to synchronize sequence numbers.

The three-way handshake is used to establish a maximum data packet size to be sent, thus minimizing the error rate.

The three-way handshake provides a global clock to establish window sizes.

TCP may have different mechanisms to choose initial sequence numbers, and therefore without the three-way handshake, sequence numbers would be out of sync.


With TCP/IP data encapsulation, which range of port numbers identifies all well-known applications?

0 to 255

256 to 1022

0 to 1023

1024 to 2047

49153 to 65535


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


Why are port numbers included in the TCP header of a segment?

to indicate the correct router interface that should be used to forward a segment

to identify which switch ports should receive or forward the segment

to determine which Layer 3 protocol should be used to encapsulate the data

to enable a receiving host to forward the data to the appropriate application

to allow the receiving host to assemble the packet in the proper order


Which OSI model layer is responsible for regulating the flow of information from source to destination, reliably and accurately?







Refer to the exhibit. Host A is using FTP to download a large file from Server 1. During the download process, Server 1 does not receive an acknowledgment from Host A for several bytes of transferred data. What action will Server 1 take as a result?

create a Layer 1 jam signal

reach a timeout and resend the data that needs to be acknowledged

send a RESET bit to the host

change the window size in the Layer 4 header


Why is flow control used for TCP data transfer?

to synchronize equipment speed for sent data

to synchronize and order sequence numbers so data is sent in complete numerical order

to prevent the receiver from being overwhelmed by incoming data

to synchronize window size on the server

to simplify data transfer to multiple hosts