CompTIA Network+ Certification Study Guide part 72 ppt

Appendix C 696 C. RF interference from other devices. D. All of the above. Correct answer and explanation: D. All of these could be a problem. Structural interference such as thick walls, metal between the access point and computer, could cause a shortening of distance. EMI environmentally could cause a shortening of distance. RFI could also cause a shortening of distance. ChApTEr 6: ThE oSI ModEl ANd NETworKING proToColS Which OSI model layer is responsible for frame sequencing?1. A. The physical layer B. The transport layer C. The data link layer D. The application layer Correct answer and explanation: C. The data link layer combines bits into bytes and bytes into frames, provides access to media using MAC addresses, and error detection. Furthermore, it provides sequencing of frames. Therefore, answer C is correct. You are a network technician assigned to install a new network 2. hub. At which layer of the OSI model does a standard hub operate? Select only one answer. A. Physical layer B. Data link layer C. Network layer D. Transport layer Correct answer and explanation: A. Hubs operate at the physical layer of the OSI model. Therefore, answer A is correct. You are a network technician assigned to install a new network 3. switch. At which layer of the OSI model does a standard switch (or bridge) operate? Select only one answer. A. Physical layer B. Data link layer C. Network layer D. Transport layer Appendix C 697 Correct answer and explanation: B. Switches and bridges operate at the data link layer of the OSI model. Therefore, answer B is correct. You are a network technician assigned to install a new network 4. router. At which layer of the OSI model does a standard router operate? Choose all that apply. A. Physical layer B. Data link layer C. Network layer D. Transport layer Correct answer and explanation: C. Routers operate at the network layer of the OSI model. Therefore, answer C is correct. Don’t get caught up with “choose all that apply,” as it’s only a distracter. Pay close attention to word- ing such as this on the Network+ exam; navigating tricky wording is also another skill that you are learning while reading this publication. Pay atten- tion to all the layers, where they lay in the model, what happens at each layer, and which devices operate where. You are a network technician assigned to install a new NIC in a 5. PC. At which layer of the OSI model does a NIC operate? Select only one answer. A. Physical layer B. Data link layer C. Network layer D. Transport layer Correct answer and explanation: B. NICs operate at the data link layer of the OSI model. Therefore, answer B is correct. What is the unique physical address (Burned in Address [BIA]) that 6. is found on all NICs called? A. DNS address B. NAT address C. IP address D. MAC address Correct answer and explanation: D. Every network adapter has a unique Media Access Control (MAC) address assigned to it. The MAC address is the unique ID serial number of the Ethernet card in one’s computer. MAC addresses are needed in a LAN for computers to communicate; therefore, answer D is correct. Note that MAC addresses have nothing to do with Apple Macintosh computers. Appendix C 698 Which of the following is a valid MAC address?7. A. 00:05:J6:0D:91:K1 B. 10.0.0.1–255.255.255.0 C. 00:05:J6:0D:91:B1 D. 00:D0:A0:5C:C1:B5 Correct answer and explanation: D. A MAC address consists of six hexadeci- mal numbers. The highest possible hexadecimal number is FF:FF:FF:FF:FF:FF, which denotes a broadcast. The first three bytes contain a manufacturer code and the last three bytes contain a unique station ID. Therefore, answer D is cor- rect. You have to understand hexadecimal to be able to solve this, as decimal is base10, binary is a base2 system, and hex is base16. The numbers are counted from 0 to 9, then lettered A to F before adding another digit. The letters A through F represent decimal numbers 10 through 15, respectively. Since F is the highest, then obviously an answer like C is easy to eliminate, as a quick scan of the hex shows a letter “J” used, which is not in the base16 numbering system. You are the system administrator for a small company that runs 8. two Windows servers (Windows Server 2003) and two Linux servers (SUSE Linux). You need to lock down the connections to the switch via port security; this essentially means you will need to retrieve the MAC addresses on the systems. MAC addresses are found on Linux server by issuing which command? A. Ipconfig/a B. Ifconfig/a C. Winipcfg/a D. Ifconfig –a Correct answer and explanation: D. It is very easy to confuse this with other system commands as they are very similar. But answer D is correct. Do not forget that Linux is ifconfig; Windows is either winipcfg or ipconfig. From the list of choices, which of the following media access 9. methods is used for an IEEE 802.5 network? A. Direct sequence B. Token passing C. CSMA/CD D. CSMA/CA Correct answer and explanation: B. The 802.5 standard defines a Token Ring network. Token Ring uses token passing as its method of communicat- ing on the network; therefore, answer B is correct. Appendix C 699 Which of the following provides NetBIOS name to IP address 10. resolution? A. Hosts B. lmhosts C. Services D. Protocols Correct answer and explanation: B. The lmhosts file contains NetBIOS name-to-IP address mappings. It is stored on local Windows workstations and acts much like a hosts file, but instead of working within DNS, the lmhosts file works with NetBIOS name-to-IP address name resolution. Therefore, answer B is correct. POP3 is identified by which TCP/IP port number?11. A. UDP Port 21 B. TCP Port 23 C. UDP Port 25 D. TCP Port 110 Correct answer and explanation: D. POP use TCP port 110. Therefore, answer D is correct. Standards for CSMA/CD are specified by which IEEE 802 sublayer?12. A. 802.1 B. 802.2 C. 802.3 D. 802.5 Correct answer and explanation: C. CSMA/CD is used on multiple access networks as defined in the IEEE 802.3 specification. Using this method, devices that have data to transmit listen for an opening on the line before transmitting (Carrier Sense). That is, they wait for a time when there are no signals traveling on the cable. When a device detects an opening, it transmits its data. Therefore, answer C is correct. From the choices listed, which of the following protocols represents 13. e-mail protocols? Please choose two from the list below. A. POP3 B. SMNP C. IMAP4 D. Telnet Correct answers and explanations: A and C. POP3, IMAP4, and SMTP are common e-mail-based protocols. Therefore, answers A and C are correct. Appendix C 700 When discussing the OSI model and the DoD model, which layers 14. of the OSI model handle what you would find in the Application layer of the DoD model? Choose all that apply. A. Application B. Presentation C. Transport D. Session Correct answers and explanations: A, B, and D. The OSI model has seven layers, and the DoD model has four. The top layer of the DoD model is the Application layer, but it also maps cleanly to the OSI model’s top three layers, application, presentation, and session. You are a network administrator looking to implement technology 15. into a company. You are told you need to build a network using the IEEE 802.11 standard. From the list below, the IEEE 802.11 stan- dard maps to which of the following? Select only one answer. A. Token Ring B. Wired Ethernet C. Metropolitan Area Network (MAN) D. Wireless in Infrastructure mode Correct answer and explanation: D. 802.11 Standards such as 802.11, 802.11b, 802.11a, and 802.11g are all related to wireless networking. Wireless technologies and infrastructure mode are covered in depth in Chapter 5, “Wireless Networking.” For this chapter, you need to master the memorization of these standards; the Network+ exam focuses on wireless technologies more now than in the past, so make sure you review this section completely. ChApTEr 7: TCp/Ip ANd rouTING You are a network administrator and you have 1,000 client com-1. puters that you need to set up with IP addressing. What protocol would you use to set up these client computers with an IP address, subnet mask, default gateway, and preferred DNS server? A. DHCP B. APIPA C. BOOTP D. TFTP Appendix C 701 Correct answer and explanation: A. DHCP would allow you to dynamically assign IP addresses and the additional options to these client computers. Incorrect answers and explanations: B, C, and D. Answer B is incorrect, Automatic Private IP addressing would not allow you to assign anything. APIPA assigns its own IP addresses. Answer C is incorrect, BOOTP can only assign an IP address and subnet mask. Answer D is incorrect, TFTP is used for transferring files. You have been given an IP address in binary form. The address 2. you have been given is 11000000.00000000.00000000.00000001. What is this IP address in decimal form? A. 127.0.0.1 B. 191.0.0.1 C. 137.0.0.1 D. 192.0.0.1 Correct answer and explanation: D. You add 128 + 64 for the first two ones to get 192. Incorrect answers and explanations: A, B, and C. Answer A is incorrect; 128 would be 01111111. Answer B is incorrect; 191 would be 10111111. Answer C is incorrect; 137 would be 10001001l. You have been asked by your colleague Bobbi about classfull IP 3. addresses. Which of the following is NOT a normal IP address class? A. CLASS A B. CLASS D C. CLASS F D. CLASS C Correct answer and explanation: C. Class F addresses do not exist. Incorrect answers and explanations: A, B, and D. Answer A is incor- rect; Class A addresses begin with 1–126. Answer B is incorrect as Class D addresses are used for multicasting and begin with 224–239. Answer D is incorrect as Class C addresses begin between 192 and 223. You have been asked to explain what a certain IP address is 4. used for. The IP address is 224.0.0.1. What are addresses in the 224.0.0.0 range used for? A. SNMP B. HTTP Appendix C 702 C. POP3 D. Multicasting Correct answer and explanation: D. Addresses that begin with 224 are used for multicasting. Incorrect answers and explanations: A, B, and C. Answer A is incorrect; this is for network management. Answer B is incorrect as this is for brows- ing the Web. Answer C is incorrect, this is for receiving e-mail. You are having a conversation with another networking profes-5. sional and the subject of protocols comes up. You are asked which of the following are IGP routing protocols. A. OSPF B. BGP C. IS–IS D. RIP Correct answer and explanation: A and D. Both OSPF and RIP are Interior Gateway Routing protocols. Incorrect answers and explanations: B and C. Answer B is incorrect; Border Gateway Protocol is an EGP. Answer C is incorrect; IS–IS is an EGP. You have been asked to lay out a new small office network. Which 6. of the following IP address ranges could you use because they are private address ranges? A. 11.0.0.0 to 11.255.255.255.255 B. 137.1.0.0 to 137.1.255.255 C. 191.4.0.0 to 191.4.255.255 D. 192.168.5.0 to 192.168.5.255 Correct answer and explanation: D. This falls into the private IP address range of 192.168.0.0 to 192.168.255.255. Incorrect answers and explanations: A, B, and C. Answer A is incorrect; this is a public class A network. Answer B is incorrect as this is a public class B network. Answer C is incorrect as this is a public class B network. You have a user who cannot get connected to the Internet. You 7. have the user run IPCONFIG/ALL and he reads you the IP address of 169.254.1.3. What is wrong with this system? A. System has a static IP address. B. System has an APIPA address. Appendix C 703 C. System has a bad address. D. System has a classless address. Correct answer and explanation: B. The system has failed to get an IP address from a DHCP server and has assigned itself an Automatic Private IP address which only allows for local communication. Incorrect answers and explanations: A, C, and D. Answer A is incorrect; the system would not have been assigned a static IP address in this range. Answer C is incorrect as this is a valid private APIPA address. Answer D is incorrect; classless addressing is not a factor in this problem. A user has been given an IP address of 192.168.1.1 with a subnet 8. mask of 255.255.255.0. How would you express the subnet mask for this address using CIDR notation? A. /24 B. /8 C. /16 D. /22 Correct answer and explanation: A. The CIDR notation expresses how many bits is a part of the subnet mask. This address has 24 bits in the sub- net mask. Incorrect answers and explanations: B, C, and D. Answer B is incor- rect as this represents 255.0.0.0. Answer C is incorrect as this represents 255.255.0.0. Answer D is incorrect as this represents 255.255.252.0. A user has been given an address of fe80::9c5f:9695:f235:0051. 9. What kind of address has she been given? A. IPv4 address B. IPv6 address C. MAC address D. GUID Correct answer and explanation: B. This is a condensed notation for a IPv6 address. The full address would be fe80:0000:0000:0000:9c5f:9695:f 235:0051. Incorrect answers and explanations: A, C, and D. Answer A is incorrect; an IPv4 address looks like this, 192.168.1.1. Answer C is incorrect; a MAC address looks like this AA:BB:CC:DD:EE:FF. Answer D is incorrect; a GUID is used in Microsoft’s Active Directory. Appendix C 704 You have a network with several thousand users. You do not want 10. to manually configure every user computer. What protocol would you use to automatically configure their IP addresses? A. SNMP B. APIPA C. DHCP D. TFTP Correct answer and explanation: C. Dynamic Host Configuration protocol allows you to automatically assign IP addresses, subnet masks, and many other options to client computers. Incorrect answers and explanations: A, B, and D. Answer A is incorrect; SNMP is for network management, not assigning IP addresses. Answer B is incorrect; APIPA has a machine assign its own IP address but does not allow for communication outside the local network. Answer D is incorrect; TFTP is for transferring files at high speeds. You have been asked to implement routing on a simple corporate 11. local area network. All connections will be at the same speed. Which routing protocol would you use for a simple network like this? A. OSPF B. RIP C. BGP D. IS-IS Correct answer and explanation: B. RIP is the most universal routing pro- tocol and has very little overhead for a local area network. Incorrect answers and explanations: A, C, and D. Answer A is incorrect; OSPF is more complicated than RIP but does factor in connections of differ- ent speeds. Answer C is incorrect; BGP is an Exterior Gateway Protocol and is designed not to be used on a LAN. Answer D is incorrect; IS–IS is designed as an Exterior Gateway Protocol. You have been asked to connect routing for your corporate network 12. to your ISP. Which routing protocol would you use for an exterior connection? A. OSPF B. RIP C. BGP D. EIGRP Appendix C 705 Correct answer and explanation: C. BGP is designed for connections such as that to your ISP. Incorrect answers and explanations: A, B, and D. Answer A is incorrect; OSPF is an IGP and is designed for LAN use. Answer B is incorrect; RIP is an IGP and is designed for LAN use. Answer D is incorrect; EIGRP is a Cisco proprietary protocol and is designed for LAN use. You have a main corporate location and several branch locations. 13. All locations access the Internet through corporate. What type of routing would you enable for this approach? A. None B. Dynamic C. Static D. Classless Correct answer and explanation: C. Static routing would be the most sim- ple and with the least amount of overhead. Incorrect answers and explanations: A, B, and D. Answer A is incorrect; you would still need some sort of routing for this network. Answer B is incorrect; dynamic routing would work, but would create overhead on the routers and network. Answer D is incorrect; classless routing just means that you are not adhering the standard subnet masks. You have a main corporate location and several branch locations. 14. All locations access the Internet through their own dedicated con- nections. What type of routing would you enable for this approach? A. None B. Dynamic C. Static D. Classless Correct answer and explanation: B. Dynamic routing would be the best choice since as the status of the Internet connections fluctuates the dynamic routing protocol would be able to redirect internet bound traffic through another facility as appropriate and with the least amount of overhead. Incorrect answers and explanations: A, C, and D. Answer A is incorrect; you would still need some sort of routing for this network. Answer C is incorrect; static routing would work, but would create overhead on the routers and net- work whenever a link to the Internet was to become unavailable and the traffic require redirection through another office location. Answer D is incorrect; class- less routing just means that you are not adhering the standard subnet masks. . all that apply,” as it’s only a distracter. Pay close attention to word- ing such as this on the Network+ exam; navigating tricky wording is also another skill that you are learning while reading. “Wireless Networking.” For this chapter, you need to master the memorization of these standards; the Network+ exam focuses on wireless technologies more now than in the past, so make sure you review. /16 D. /22 Correct answer and explanation: A. The CIDR notation expresses how many bits is a part of the subnet mask. This address has 24 bits in the sub- net mask. Incorrect answers and explanations: