Cisco CCNA IPv4 and IPv6 Addressing 3 — Questions and Answers
Question 1: Which of the following is a valid IPv6 link-local address prefix?
- FC00::/7
- FE80::/10 (Correct answer)
- FF00::/8
- 2001::/32
Correct answer: FE80::/10
Link-local addresses always start with FE80::/10 and are automatically assigned to every IPv6-enabled interface.
Question 2: What does the 'network address' of a subnet represent?
- The first usable host address
- The address assigned to the default gateway
- The base address that identifies the subnet itself (Correct answer)
- The last address in the subnet range
Correct answer: The base address that identifies the subnet itself
The network address (all host bits set to 0) identifies the subnet and cannot be assigned to a host.
Question 3: An interface receives the IPv6 address 2001:DB8::1/64 via stateless address autoconfiguration (SLAAC). Which portion is derived from the router advertisement?
- The full 128-bit address
- The last 64 bits (interface ID)
- The first 64 bits (prefix) (Correct answer)
- The /64 prefix length only
Correct answer: The first 64 bits (prefix)
SLAAC uses the 64-bit prefix advertised by the router and the device generates its own 64-bit interface ID (typically from the EUI-64 process).
Question 4: Which private IPv4 address range is defined in RFC 1918 for Class B networks?
- 10.0.0.0 – 10.255.255.255
- 172.16.0.0 – 172.31.255.255 (Correct answer)
- 192.168.0.0 – 192.168.255.255
- 169.254.0.0 – 169.254.255.255
Correct answer: 172.16.0.0 – 172.31.255.255
RFC 1918 designates 172.16.0.0 through 172.31.255.255 (172.16.0.0/12) as private Class B space.
Question 5: How many usable host addresses are available in a /29 subnet?
- 6 (Correct answer)
- 14
- 30
- 8
Correct answer: 6
A /29 subnet has 3 host bits (2^3 = 8 addresses), minus 2 for network and broadcast, leaving 6 usable hosts.
Question 6: Which IPv6 multicast address is used to reach all routers on the local link?
- FF02::1
- FF02::2 (Correct answer)
- FF02::5
- FF02::9
Correct answer: FF02::2
FF02::2 is the all-routers multicast address scoped to the local link.
Question 7: Which IPv4 address is reserved as the limited broadcast address?
- 0.0.0.0
- 127.0.0.1
- 255.255.255.255 (Correct answer)
- 224.0.0.1
Correct answer: 255.255.255.255
255.255.255.255 is the limited broadcast address used to reach all hosts on the local network segment without routing.
Cisco CCNA IPv4 and IPv6 Addressing 3
Which of the following is a valid IPv6 link-local address prefix?