CCNA_Sybex_2.txt

  1. 1. What are the decimal and hexadecimal equivalents of the binary number 10011101? (Choose two.) A. 159 B. 157 C. 185 D. 0x9D E. 0xD9 F. 0x159
    B, D. To turn a binary number into decimal, you just have to add the values of each bit that is a 1. The values of 10011101 are 128, 16, 8, 4, and 1. 128 + 16 + 8 + 4 + 1 = 157. Hexadecimal is a base-16 number system. The values of hexadecimal are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F—16 characters total, from which to create all the numbers you’ll ever need. So, if 1001 in binary is 9, then the hexadecimal equivalent is 9. Since we then have 1101, which is 13 in binary, the hexadecimal answer is D and the complete hexadecimal answer is 0x9D.
  2. 2. Which of the following allows a router to respond to an ARP request that is intended for a remote host? A. Gateway DP B. Reverse ARP (RARP) C. Proxy ARP D. Inverse ARP (IARP) E. Address Resolution Protocol (ARP)
    C. Proxy ARP can help machines on a subnet reach remote subnets without configuring routing or a default gateway.
  3. 3. You want to implement a mechanism that automates the IP configuration, including IP address, subnet mask, default gateway, and DNS information. Which protocol will you use to accomplish this? A. SMTP B. SNMP C. DHCP D. ARP
    C. Dynamic Host Configuration Protocol (DHCP) is used to provide IP information to hosts on your network. DHCP can provide a lot of information, but the most common is IP address, subnet mask, default gateway, and DNS information.
  4. 4. What protocol is used to find the hardware address of a local device? A. RARP B. ARP C. IP D. ICMP E. BootP
    B. Address Resolution Protocol (ARP) is used to find the hardware address from a known IP address.
  5. 5. Which of the following are layers in the TCP/IP model? (Choose three.) A. Application B. Session C. Transport D. Internet E. Data Link F. Physical
    A, C, D. This seems like a hard question at first because it doesn’t make sense. The listed answers are from the OSI model and the question asked about the TCP/IP protocol stack (DoD model). However, let’s just look for what is wrong. First, the Session layer is not in the TCP/ IP model; neither are the Data Link and Physical layers. This leaves us with the Transport layer (Host-to-Host in the DoD model), Internet layer (Network layer in the OSI), and Application layer (Application/Process in the DoD).
  6. 6. Which class of IP address provides a maximum of only 254 host addresses per network ID? A. Class A B. Class B C. Class C D. Class D E. Class E
    C. A Class C network address has only 8 bits for defining hosts: 28 – 2 = 254.
  7. 7. Which of the following describe the DHCP Discover message? (Choose two.) A. It uses FF:FF:FF:FF:FF:FF as a layer 2 broadcast. B. It uses UDP as the Transport layer protocol. C. It uses TCP as the Transport layer protocol. D. It does not use a layer 2 destination address.
    A, B. A client that sends out a DHCP Discover message in order to receive an IP address sends out a broadcast at both layer 2 and layer 3. The layer 2 broadcast is all Fs in hex, or FF:FF:FF:FF:FF:FF. The layer 3 broadcast is 255.255.255.255, which means all networks and all hosts. DHCP is connectionless, which means it uses User Datagram Protocol (UDP) at the Transport layer, also called the Host-to-Host layer.
  8. 8. Which layer 4 protocol is used for a Telnet connection? A. IP B. TCP C. TCP/IP D. UDP E. ICMP
    B. Although Telnet does use TCP and IP (TCP/IP), the question specifically asks about layer 4, and IP works at layer 3. Telnet uses TCP at layer 4.
  9. 9. Which statements are true regarding ICMP packets? (Choose two.) A. They acknowledge receipt of a TCP segment. B. They guarantee datagram delivery. C. They can provide hosts with information about network problems. D. They are encapsulated within IP datagrams. E. They are encapsulated within UDP datagrams.
    C, D. Internet Control Message Protocol (ICMP) is used to send error messages through the network, but they do not work alone. Every segment or ICMP payload must be encapsulated within an IP datagram (or packet).
  10. 10. Which of the following services use TCP? (Choose three.) A. DHCP B. SMTP C. SNMP D. FTP E. HTTP F. TFTP
    B, D, E. SMTP, FTP, and HTTP use TCP.
  11. 11. Which of the following services use UDP? (Choose three.) A. DHCP B. SMTP C. SNMP D. FTP E. HTTP F. TFTP
    A, C, F. Explanation: DHCP, SNMP, and TFTP use UDP. SMTP, FTP, and HTTP use TCP.
  12. 12. Which of the following are TCP/IP protocols used at the Application layer of the OSI model? (Choose three.) A. IP B. TCP C. Telnet D. FTP E. TFTP
    C, D, E. Telnet, File Transfer Protocol (FTP), and Trivial FTP (TFTP) are all Application layer protocols. IP is a Network layer protocol. Transmission Control Protocol (TCP) is a Transport layer protocol.
  13. 13. The following illustration shows a data structure header. What protocol is this header from? A. IP B. ICMP C. TCP D. UDP E. ARP F. RARP Bit 0 Bit 15 Bit 16 Bit 31 Source port (16) Destination port (16) Sequence number (32) Acknowledgment number (32) Header length (4) Reserved (6) Code bits (6) Window (16) Checksum (16) Urgent (16) Options (0 or 32 if any) Data (varies) 24 bytes
    C. First, you should know easily that only TCP and UDP work at the Transport layer, so now you have a 50/50 shot. However, since the header has sequencing, acknowledgment, and win- dow numbers, the answer can only be TCP.
  14. 14. If you use either Telnet or FTP, which is the highest layer you are using to transmit data? A. Application B. Presentation C. Session D. Transport
    A. Both FTP and Telnet use TCP at the Transport layer; however, they both are Application layer protocols, so the Application layer is the best answer for this question.

    • 15. The DoD model (also called the TCP/IP stack) has four layers. Which layer of the DoD model is equivalent to the Network layer of the OSI model? A. Application B. Host-to-Host C. Internet D. Network Access
    • C. The four layers of the DoD model are Application/Process, Host-to-Host, Internet, and Network Access. The Internet layer is equivalent to the Network layer of the OSI model.
  15. 16. Which two of the following are private IP addresses? A. 12.0.0.1 B. 168.172.19.39 C. 172.20.14.36 D. 172.33.194.30 E. 192.168.24.43
    C, E. Class A private address range is 10.0.0.0 through 10.255.255.255. Class B private address range is 172.16.0.0 through 172.31.255.255, and Class C private address range is 192.168.0.0 through 192.168.255.255.
  16. 17. What layer in the TCP/IP stack is equivalent to the Transport layer of the OSI model? A. Application B. Host-to-Host C. Internet D. Network Access
    B. The four layers of the TCP/IP stack (also called the DoD model) are Application/Process, Host-to-Host, Internet, and Network Access. The Host-to-Host layer is equivalent to the Transport layer of the OSI model.
  17. 18. Which statements are true regarding ICMP packets? (Choose two) A. ICMP guarantees datagram delivery. B. ICMP can provide hosts with information about network problems. C. ICMP is encapsulated within IP datagrams. D. ICMP is encapsulated within UDP datagrams.
    B, C. ICMP is used for diagnostics and destination unreachable messages. ICMP is encapsulated within IP datagrams, and because it is used for diagnostics, it will provide hosts with information about network problems.
  18. 19. What is the address range of a Class B network address in binary? A. 01xxxxxx B. 0xxxxxxx C. 10xxxxxx D. 110xxxxx
    C. The range of a Class B network address is 128–191. This makes our binary range 10xxxxxx.
  19. 20. Which of the following protocols uses both TCP and UDP? A. FTP B. SMTP C. Telnet D. DNS
    D. DNS uses TCP for zone exchanges between servers and UDP when a client is trying to resolve a hostname to an IP address.
Author
gjpmp3
ID
49271
Card Set
CCNA_Sybex_2.txt
Description
CCNA Sybex Ch1 questions
Updated