Testking_640-802_V13

Explanation:

Only network address contains this information. To transmit the packets the sender uses network address and datalink address. But the layer 2 address represents just the address of the next hop device on the way to the sender. It is changed on each hop. Network address remains the same.

QUESTION NO: 9

Which of the following correctly describe steps in the OSI data encapsulation process? (Choose two)

A.The presentation layer translates bits into voltages for transmission across the physical link.

B.The transport layer divides a data stream into segments and adds reliability and flow control information.

C.Packets are created when the network layer adds Layer 3 addresses and control information to a segment.

D.The data link layer adds physical source and destination addresses and an FCS to the segment.

E.Packets are created when the network layer encapsulates a frame with source and destination host addresses and protocol-related control information.

Answer: B, C

Explanation:

The Transport Layer:

You can think of the transport layer of the OSI model as a boundary between the upper and lower protocols. The transport layer provides a data transport service that shields the upper layers from transport implementation issues such as the reliability of a connection. The transport layer provides mechanisms for:

The Network Layer:

Layer three of the OSI model is the network layer.

network.

Leading the way in IT testing and certification tools, www.testking.com

- 21 -

packets.

Incorrect Answers:

A: This correctly describes the physical layer, not the presentation layer.

D:Although the data link layer adds physical (MAC) source and destination addresses, it adds it to a frame, not a segment.

E:Packets are encapsulated, not frames.

QUESTION NO: 10

When files are transferred between a host and an FTP server, the data is divided into smaller pieces for transmission. As these pieces arrive at the destination host, they must be reassembled to reconstruct the original file. What provides for the reassembly of these pieces into the correct order?

A.The sequence number in the TCP header

B.The Start Frame Delimiter in the 802.3 Preamble

C.The TTL in the IP header

D.The acknowledgement number in the segment header

E.The frame check sequence in the Ethernet frame trailer

Answer: A Explanation:

The Transport layer can provide reliable networking via acknowledgments, sequencing, and flow control.

Acknowledgments Delivered segments are acknowledged to the sender. If they are not acknowledged, the sender will retransmit.

Sequencing Data segments are sequenced into their original order when they arrive at the destination.

Flow Control Provides buffer controls that prevent packet flooding to the destination host. Buffers store bursts of data for processing when the transmission is complete.

Layer 4 protocols include the following: Transmission Control Protocol (TCP) User Datagram Protocol (UDP)

Sequenced Packet Exchange (SPX)A reliable communications protocol created by Novell NetWare

QUESTION NO: 11 DRAG DROP

You work as a network administrator at TestKing.com.

Leading the way in IT testing and certification tools, www.testking.com

- 22 -

Your boss, Mrs. Tess King, is interested in the OSI layers. Match the terms with the appropriate layer. Some options are not used.

Answer:

Explanation:

Leading the way in IT testing and certification tools, www.testking.com

- 23 -

QUESTION NO: 12

Refer to the following exhibit:

Leading the way in IT testing and certification tools, www.testking.com

- 24 -

What data structure is described in the exhibit shown above?

A.IP datagram

B.TCP segment

C.Ethernet frame

D.UDP datagram

E.FDDI frame

F.Token Ring frame

G.None of the above

Answer: B Explanation:

The Figure below illustrates the fields and overall format of a TCP packet.

Twelve fields comprise a TCP packet.

Leading the way in IT testing and certification tools, www.testking.com

- 25 -

The following descriptions summarize the TCP packet fields illustrated above.

1. SourcePort and DestinationPort-Identifies points at which upper-layer source and destination processes receive TCP services.

2.

3. Sequence Number-Usually specifies the number assigned to the first byte of data in the current message. In the connection-establishment phase, this field also can be used to identify an initial sequence number to be used in an upcoming transmission.

4.

5. Acknowledgment Number-Contains the sequence number of the next byte of data the sender of the packet expects to receive.

6.

7. Data Offset-Indicates the number of 32-bit words in the TCP header. 8.

9. Reserved-Remains reserved for future use.

10.

11.Flags-Carries a variety of control information, including the SYN and ACK bits used for connection establishment, and the FIN bit used for connection termination.

12.

13. Window-Specifies the size of the sender's receive window (that is, the buffer space available for incoming data).

14.

15. Checksum-Indicates whether the header was damaged in transit. 16.

Leading the way in IT testing and certification tools, www.testking.com

- 26 -

17. Urgent Pointer-Points to the first urgent data byte in the packet. 18.

19. Options-Specifies various TCP options. Data-Contains upper-layer information.

Section 4: Describe common networked applications including web applications (4 questions)

QUESTION NO: 1

Part of the TestKing network is displayed below:

Study the exhibit shown above. Host TestKingA has established a connection with the TestKingII server attached to interface E0 of the TestKing2 router. Which of the following statements describe the information contained in protocol data units sent from Host TestKing to TestKingII? (Choose three)

A.The destination port number in a segment header will have a value of 80

B.The destination IP address of a packet will be the IP address of the E0 interface of the TestKing1 router

Leading the way in IT testing and certification tools, www.testking.com

- 27 -

C.The destination IP address of a packet will be the IP address of the network interface of the TestKingII server

D.The destination address of a frame will be the MAC address of the E0 interface of TestKing1 router

Answer: A, C, D

QUESTION NO: 2

You have just installed a new web server on the Testking network. You are required to ensure that the web server is accessible from the Internet. The network uses private addressing, so an IP-to-registered address mapping is required.

To do this, you enter the following command:

TestKing(config)# ip nat inside source static 192.168.2.1 198.18.1.254

You unsuccessfully try to ping the Internet from a PC host on the LAN. During the troubleshooting process, you enter the "show ip nat translations" command but the output is blank.

What is the most likely cause of the problem?

A.The keyword overload is missing from the command.

B.The NAT pool must be defined first.

C.An access list must be defined to create static NAT translations.

D.The interfaces must be configured for NAT.

E.None of the above

Answer: D Explanation:

In order to successfully configure a static NAT translation, the interfaces must be configured for NAT, in addition to the global NAT command that was entered. The router interface that lies on the inside part of the network must be defined using the "ip nat inside" command. Similarly, the WAN interface that is being used for the Internet connection must be defined using the "ip nat outside" command.

Incorrect Answers:

Leading the way in IT testing and certification tools, www.testking.com

- 28 -

A. In order to make an internal server reachable from the Internet, a static one to one NAT entry must be configured for the server. The keyword "overload" is used to configure many to one NAT, or PAT.

B, C. This need not be done in order to create a static NAT entry. These steps are typically done in setting up NAT so that inside LAN users can access the Internet via NAT.

QUESTION NO: 3

Which protocol below uses TCP port 443 at layer 4?

A.HTML

B.HTTPS

C.TFTP

D.Telnet

E.SMTP

F.None of the above

Answer: B Explanation:

HTTPS is the secured version of the HTTP application, which normally uses 128 bit SSL encryption to secure the information sent and received on a web page. An example is a banking web site, or a trustworthy shopping web site that takes credit card information. It is an application layer protocol which uses TCP port 443.

Incorrect Answers:

A. HTML is not a protocol.

C.TFTP uses UDP port 69.

D.Telnet uses TCP port 23.

E.SMTP uses TCP port 25.

QUESTION NO: 4

As a CCNA candidate, you will be expected to know the OSI model very well. Which of the following are associated with the application layer (layer 7) of the OSI model? (Choose two)

A.TCP

B.Telnet

C.FTP

Leading the way in IT testing and certification tools, www.testking.com

- 29 -

D.Ping

E.IP

F.UDP

Answer: B, C

Explanation:

The application layer is the top layer of the OSI model and is used to describe the end user applications that can be used over a network.

Layer Name Examples

Application (layer 7) Telnet, HTTP, FTP, WWW browsers, NFS, SMTP gateways, SNMP

Incorrect Answers:

A. TCP resides at layer 4.

D.ARP is a function of the data link layer, which is layer 2.

E.IP is used at layer 3 (network layer).

Reference: CCNA Self-Study CCNA INTRO exam certification Guide (Cisco Press, ISBN 1-58720-094-5) Page 34.

Section 5: Describe the purpose and basic operation of the protocols in the OSI and TCP models (13 questions)

QUESTION NO: 1

As the TestKing network administrator, you are required to have a firm understanding of the OSI model. Why does the data communication industry use the layered OSI reference model? (Choose two)

A.It enables equipment from different vendors to use the same electronic components, thus saving research and development funds

B.It encourages industry standardization by defining what functions occur at each layer of the model

C.It divides the network communication process into smaller and simpler components; thus aiding component development, design and troubleshooting

D.It provides a means by which changes in functionality in one layer require changes in other layers

E.It supports the evolution of multiple competing standards and thus provides business opportunities for equipment manufacturers

Leading the way in IT testing and certification tools, www.testking.com

- 30 -