CCNA Routing and Switching Complete Study Guide. Todd Lammle
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30. C. An inside global address is considered to be the IP address of the host on the private network after translation. See Chapter 13 for more information.
31. B. Once you create your pool, the command ip nat inside source must be used to say which inside locals are allowed to use the pool. In this question, we need to see if access list 100 is configured correctly, if at all, so show access-list is the best answer. See Chapter 13 for more information.
32. D. Layer 2 switching creates individual collision domains per port. See Chapter 1 for more information.
33. C. The command line vty 0 4 places you in a prompt that will allow you to set or change your Telnet password. See Chapter 6 for more information.
34. B. To see the contents of all access lists, use the show access-lists command. See Chapter 12 for more information.
35. C. VLANs break up broadcast domains at layer 2. See Chapter 11 for more information.
36. A. The command erase startup-config deletes the configuration stored in NVRAM. See Chapter 6 for more information.
37. C. ICMP is the protocol at the Network layer that is used to send messages back to an originating router. See Chapter 3 for more information.
38. A. Class A addressing provides 22 bits for host subnetting. Class B provides 16 bits, but only 14 are available for subnetting. Class C provides only 6 bits for subnetting. See Chapter 3 for more information.
39. B. Only the EIGRP route will be placed in the routing table because EIGRP has the lowest administrative distance (AD), and that is always used before metrics. See Chapter 8 for more information.
40. D. Switches send information about only one VLAN down a link unless it is configured as a trunk link. See Chapter 11 for more information.
41. B, G. To enable OSPF, you must first start OSPF using a process ID. The number is irrelevant; just choose a number from 1 to 65,535 and you're good to go. After you start the OSPF process, you must configure interfaces on which to activate OSPF using the network command with wildcards and specification of an area. Option F is wrong because there must be a space after the parameter area and before you list the area number. See Chapter 9 for more information.
42. A. By default, switches break up collision domains on a per-port basis but are one large broadcast domain. See Chapter 1 for more information.
43. B. At the moment of OSPF process startup, the highest IP address on any active interface will be the router ID (RID) of the router. If you have a loopback interface configured (logical interface), then that will override the interface IP address and become the RID of the router automatically. See Chapter 18 for more information.
44. C, D. VLAN Trunking Protocol (VTP) is not right because it has nothing to do with trunking except that it sends VLAN information across a trunk link. 802.1q and ISL encapsulations are used to configure trunking on a port. See Chapter 11 for more information.
45. D. Stub networks have only one connection to an internetwork. Default routes should be set on a stub network or network loops may occur; however, there are exceptions to this rule. See Chapter 9 for more information.
46. B. Hubs regenerate electrical signals, which are specified at the Physical layer. See Chapter 1 for more information.
47. A, C. Standard and extended access control lists (ACLs) are used to configure security on a router. See Chapter 12 for more information.
48. C. If you start at 192.168.128.0 and go through 192.168.159.0, you can see that this is a block of 32 in the third octet. Since the network address is always the first one in the range, the summary address is 192.168.128.0. What mask provides a block of 32 in the third octet? The answer is 255.255.224.0, or /19. See Chapter 5 for more information.
49. B. The command to back up the configuration on a router is copy running-config startup-config. See Chapter 7 for more information.
50. C. IEEE 802.3ab is the standard for 1 Gbps on twisted-pair. See Chapter 2 for more information.
51. C. User Datagram Protocol is a connection network service at the Transport layer, and DHCP uses this connectionless service. See Chapter 3 for more information
52. E. The clock rate command is two words, and the speed of the line is in bits per second (bps). See Chapter 6 for more information.
53. C. The show ip interface command will show you if any interfaces have an outbound or inbound access list set. See Chapter 12 for more information.
54. C. Unlike ISL, which encapsulates the frame with control information, 802.1q inserts an 802.1q field along with tag control information. See Chapter 11 for more information.
55. C. The PDU encapsulation method defines how data is encoded as it goes through each layer of the TCP/IP model. Data is segmented at the Transport later, packets created at the Network layer, frames at the Data Link layer, and finally, the Physical layer encodes the 1s and 0s into a digital signal. See Chapter 2 for more information.
56. A. With a multilayer switch, enable IP routing and create one logical interface for each VLAN using the interface vlan number command and you're now doing inter-VLAN routing on the backplane of the switch! See Chapter 11 for more information.
Part 1
ICND1
Chapter 1
Internetworking
THE FOLLOWING ICND1 EXAM TOPICS ARE COVERED IN THIS CHAPTER:
Let’s start by defining exactly what an internetwork is: You create an internetwork when you connect two or more networks via a router and configure a logical network addressing scheme with a protocol such as IP or IPv6.
We’ll also dissect the Open Systems Interconnection (OSI) model, and I’ll describe each part of it to you in detail because you really need complete, reliable knowledge of it. Understanding the OSI model is key for the solid foundation you’ll need to build upon with the more advanced Cisco networking knowledge gained as you become increasingly more skilled.
The OSI model has seven hierarchical layers that were developed to enable different networks to communicate reliably between disparate systems. Since this book is centering upon all things CCNA, it’s crucial for you to understand the OSI model as Cisco sees it, so that’s how I’ll be presenting the seven layers to you.
After you finish reading this chapter, you’ll encounter review questions and written labs. These