CCNA1 Exarm Chapter4

1. Refer to the exhibit. What two pieces of information can be determined from
the output that is shown? (Choose two.)

   The local host is using well-known port numbers to identify the source ports.
    *A termination request has been sent to 192.135.250.10.
   Communication with 64.100.173.42 is using HTTP Secure.
   *The local computer is accepting HTTP requests.
   192.168.1.101:1042 is performing the three-way handshake with 128.107.229.50:80.

2. After a web browser makes a request to a web server that is listening to the standard port,
what will be the source port number in the TCP header of the response from the server?

    13
    53
   *80
   1024
   1728

3. Which information is found in both the TCP and UDP header information?

   sequencing
   flow control
   acknowledgments
   *source and destination

4. Which is an important characteristic of UDP?

    acknowledgement of data delivery
    *minimal delays in data delivery
    high reliability of data delivery
    same order data delivery

5. 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

6. Refer to the exhibit. In line 7 of this Wireshark capture, what TCP operation is being performed?

   *session establishment   segment retransmit
   data transfer
   session disconnect

7. Refer to the exhibit. The initial TCP exchange of data between two hosts is shown in the exhibit.
Assuming an initial sequence number of 0, what sequence number will be included in
Acknowledgment 2 if Segment 6 is lost?

    2
    3
    6
    *1850
    3431
    3475

8. 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

9. During a TCP communication session, if the packets arrive to the destination out of order,
what will happen to the original message?

    The packets will not be delivered.
    The packets will be retransmitted from the source.
    *The packets will be delivered and reassembled at the destination.
    The packets will be delivered and not reassembled at the destination.

10. 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

11. Which transport layer protocol provides low overhead and would be used for applications
which do not require reliable data delivery?

    TCP
    IP
    *UDP
    HTTP
    DNS

12. What are two features of the User Datagram Protocol (UDP)? (Choose two.)

    flow control
    *low overhead
    *connectionless
    connection-oriented
    sequence and acknowledgements

13. What mechanism is used by TCP to provide flow control as segments travel from
source to destination?

    sequence numbers
    session establishment
    *window size
    acknowledgments

14. What is dynamically selected by the source host when forwarding data?

     destination logical address
     source physical address
     default gateway address
     *source port

15. 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

16. Which two options represent Layer 4 addressing? (Choose two.)

      identifies the destination network
      identifies source and destination hosts
     *identifies the communicating applications
     *identifies multiple conversations between the hosts
      identifies the devices communicating over the local media

17. Which three features allow TCP to reliably and accurately track the transmission
of data from source to destination?(Choose three.)

     encapsulation
     *flow control
     connectionless services
    *session establishment
    *numbering and sequencing
    best effort delivery

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

    application
    presentation
    session
    *transport
    network

19. 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.

20. Which event occurs during the transport layer three-way handshake?

      The two applications exchange data.
      *TCP initializes the sequence numbers for the sessions.
      UDP establishes the maximum number of bytes to be sent.
      The server acknowledges the bytes of data received from the client.