Ccna certification Practice Tests

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Appendix 

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  Answers to Practice Test Questions

 125.  B.  IGMP, or Internet Group Messaging Protocol, allows switches to join computers to 

the multicast group table. This allows the selective process of snooping to occur when 

a transmission is sent. Internet Control Message Protocol (ICMP) is used by IP utilities 

such as traceroute and ping for diagnostics and troubleshooting. Intelligent Platform 

Management Interface (IPMI) allows systems to be monitored and managed at the 

hardware level, independent of the CPU, memory, BIOS, and operating system. IPGRP is 

not a protocol that defines a standard, and therefore, it is an incorrect answer.

 126.  B.  IPv4 allows for 2

32

 = 4.3 billion addresses. However, only 3.7 billion are usable 

because of reservations and classful addressing. The current IPv4 address space is 

exhausted, and IPv6 allows for 2

128

 = 3.4 × 10

38

 addresses. IPv6 still requires NAT for 

backward compatibility with IPv4. Although IPv4 is slowly being replaced with IPv6, IPv4 

is still dominant in networks and the Internet. IPv6 does not need to be subnetted like 

IPv4 by borrowing bits from the network mask; there are 16 bits dedicated for subnets.