CH9 - IPv6 Design - Q&A

Fill in the blank: IPv6 ND is similar to what _______ does for IPv4 networks.

ARP

NAT-PT translates between what address types? a. Translates RFC 1918 private addresses to public IPv4 addresses b. Translates between IPv4 and IPv6 addresses c. Translates between network addresses and IPv6 ports d. Translates between private IPv6 addresses to public IPv6 addresses

B

What is the hierarchy for IPv6 aggregatable addresses? a. Global, site, loop b. Public, site, interface c. Internet, site, interface d. Multicast, anycast, unicast

B

What protocol numbers are used by Ethernet to identify IPv4 versus IPv6? a. Protocol 6 for IPv4 and protocol 17 for IPv6. b. 0x86DD for IPv6 and 0x0800 for IPv4. c. 0x8000 for IPv4 and 0x86DD for IPv6. d. 0x0800 for both IPv4 and IPv6; they are identified in the packet layer.

B

True or false: DHCP is required for dynamic allocation of IPv6 addresses.

False

True or false: OSPFv2 supports IPv6.

False. OSPFv3 supports IPv6. OSPFv2 is used in IPv4 networks.

True or false: DNS AAAA records are used in IPv6 networks for name-to-IPv6-address resolution.

True

True or false: ISATAP allows tunneling of IPv6 through IPv4 networks

True

The first field of the IPv6 header is 4 bits in length. What binary number is it always set to?

0110. The first field of the IPv6 header is the version field. It is set to binary 0110 (6).

IPv6 multicast addresses begin with what hexadecimal numbers?

0xFF (1111 1111 binary).

How many bits are there between the colons of IPv6 addresses?

16

What is the subnet prefix of 2001:1:0:ab0:34:ab1:0:1/64?

2001:1:0:ab0::/64.

The IPv6 address has 128 bits. How many hexadecimal numbers does an IPv6 address have?

32

What does one-to-nearest communication mean for IPv6? a. Anycast b. Broadcast c. Multicast d. Unicast

A

Which IPv6 feature enables routing to distribute connection requests to the nearest content server? a. Anycast b. Link-local c. Aggregatable d. Multicast e. Site-local

A

You have duplicate file servers at multiple locations. Which IPv6 address type allows each end station to send a request to the nearest file server using the same destination address, regardless of the location of that end station? a. Anycast b. Broadcast c. Unicast d. Global unicast e. Multicast

A

In a network where IPv6 exists within an IPv4 network, which two strategies allow both schemes to coexist? (Select two.) a. Translate between the protocols. b. Hosts run IPv4 and routers run native IPv6. c. Encapsulate IPv6 packets into IPv4 packets. d. Enable anycast in the routing protocol. e. Redistribute between the IPv4 and IPv6 networks.

A C

Which of the following describe the IPv6 header? (Select two.) a. It is 40 bytes in length. b. It is of variable length. c. The Protocol Number field describes the upper-layer protocol. d. The Next Header field describes the upper-layer protocol.

A D

Which are transition models to IPv6 for an enterprise network? a. Dual-stack b. Top-down c. Tunneled d. Service block e. Translation f. Fork-lift g. Hybrid

A, C, E. Dual-stack, tunneled, and translation are transition models to IPv6.

Which are deployment models to IPv6 for an enterprise network? a. Dual-stack b. Top-down c. Tunneled d. Service block e. Translation f. Fork-lift g. Hybrid

A, D, G. Dual-stack, service block, and hybrid are deployment models to IPv6.

How would you summarize the networks listed below? 2001:0db8:2a3e:4490::/64 2001:0db8: 2a3e:4a1b::/64 2001:0db8: 2a3e:4ff2::/64 2001:0db8: 2a3e:4c5b::/64 a. 2001:0db8:2a3e:4000::/52 b. 2001:0db8: 2a3e:4000::/56 c. 2001:0db8: 2a3e:4000::/60 d. 2001:0db8: 2a3e:4000::/64

A. All the networks can be summarized with a 52-bit mask.

A packet sent to an anycast address reaches what? a. The nearest destination in a set of hosts b. All destinations in a set of hosts c. Broadcasts to all hosts d. Global unicast destinations

A. Anycast addresses reach the nearest destination in a group of hosts.

Which of the following is an "IPv4-compatible" IPv6 address? a. ::180.10.1.1 b. f000:0:0:0:0:0:180.10.1.1 c. 180.10.1.1:: d. 2010::180.10.1.1

A. IPv4-compatible IPv6 addresses have the format ::d.d.d.d.

If an application uses broadcast traffic for IPv4, how will it communicate using IPv6? a. Anycast b. Broadcast c. Multicast d. Unicast

A. IPv6 anycast type addresses replace IPv4 broadcasts.

When using the dual-stack backbone, which of the following statements is correct? a. The backbone routers have IPv4/IPv6 dual stacks, and end hosts do not. b. The end hosts have IPv4/IPv6 dual stacks, and backbone routers do not. c. Both the backbone routers and end hosts have IPv4/IPv6 dual stacks. d. Neither the backbone routers nor end hosts have IPv4/IPv6 dual stacks.

A. The dual-stack backbone routers handle packets between IPv4 hosts and IPv6 hosts.

Which two link-state routing protocols support IPv6 routing? a. RIPng b. OSPF c. EIGRP d. IS-IS e. BGP4+

B and D. Only OSPF and IS-IS are link-state routing protocols.

What is a compact representation of the address 3f00:0000:0000:a7fb:0000:0000:b100:0023? a. 3f::a7fb::b100:0023 b. 3f00::a7fb:0000:0000:b100:23 c. 3f::a7fb::b1:23 d. 3f00:0000:0000:a7fb::b1:23

B. Answers A and C are incorrect because you cannot use the double colons (::) twice. Answers C and D are also incorrect because you cannot reduce b100 to b1.

How does a dual-stack host know which stack to use to reach a destination? a. It performs an ND, which returns the destination host type. b. It performs a DNS request that returns the IP address. If the returned address is IPv4, the host uses the IPv4 stack. If the returned address is IPv6, the host uses the IPv6 stack. c. The IPv6 stack makes a determination. If the destination is IPv4, the packet is sent to the IPv4 stack. d. The IPv4 stack makes a determination. If the destination is IPv6, the packet is sent to the IPv6 stack.

B. DNS indicates which stack to use. DNS A records return IPv4 addresses. DNS AAAA records return IPv6 addresses.

Which of the following is not an IPv6 address type? a. Unicast b. Broadcast c. Anycast d. Multicast

B. IPv6 address types are unicast, anycast, and multicast.

Which of the following are IPv6 enhancements over IPv4? a. Larger address space, globally private IP address, multicast b. Larger address space, globally unique IP addresses, no broadcasts c. Larger address space, globally private IP address, multicast d. Larger address space, address auto-configuration, enhanced broadcasts

B. IPv6 increases the address space, which allows globally unique IP addresses. Broadcasts are no longer used.

Which statement is correct? a. IPv6 does not use multicast addresses. b. IPv6 routers do not forward packets if the packet has a link-local source address. c. DHCPv6 is the only method for dynamic address assignment. d. IPv6 routers forward packets if the packet has a link-destination address.

B. Link-local source addresses remain with the local link.

What is the IPv6 equivalent to 127.0.0.1? a. 0:0:0:0:0:0:0:0 b. 0:0:0:0:0:0:0:1 c. 127:0:0:0:0:0:0:1 d. FF::1

B. The IPv6 loopback address is ::1.

What IPv6 address scope type replaces the IPv4 broadcast address? a. Unicast b. Multicast c. Broadcast d. Anycast

B. The IPv6 multicast address type handles broadcasts.

Which regional registry allocates address blocks in the Middle East? a. IANA b. RIPE c. ARIN d. APNIC e. LACNIC f. AFRINIC

B. The Réseaux IP Européens Network Coordination Centre allocates address blocks for Europe, Russia, the Middle East, and Central Asia.

Which of the following supports routing on IPv6 networks? a. RIPv3, OSPFv3, EIGRP for IPv6 b. RIPng, OSPFv3, EIGRPv6 c. RIPng, OSPFv3, EIGRP for IPv6 d. RIPv2, OSPFv2, EIGRP

C

Which statement best describes the efficiency of the IPv6 header? a. It is less efficient than the IPv4 header. b. It has the same efficiency as the IPv4 header; the larger IPv6 address makes it faster. c. It is more efficient than the IPv4 header. d. It is larger than the IPv4 header.

C

Which statements about IPv6 addresses are true? (Select two.) a. Leading 0s are required. b. Two colons (::) are used to separate fi elds. c. Two colons (::) are used to represent successive hexadecimal fields of 0s. d. A single interface will have multiple IPv6 addresses of different types.

C D

What is the compact format of the address 2102:0010:0000:0000:0000:fc23:0100:00ab? a. 2102:10::fc23:01:ab b. 2102:001::fc23:01:ab c. 2102:10::fc23:100:ab d. 2102:0010::fc23:01:ab

C. Answers A, B, and D are incorrect because 0100 does not compact to 01. Answer B is also incorrect because 0010 does not compact to 001.

IPv6 uses how many more bits for addresses than IPv4? a. 32 b. 64 c. 96 d. 128

C. IPv6 uses 128 bits for addresses, and IPv4 uses 32 bits. The difference is 96

Which IPv6 feature allows a single node to send packets that are routed to the nearest receiver from a group of potential receivers? a. Link-local b. Site-local c. Anycast d. Multicast

C. Link-local and site-local are unicast addresses, and multicast addresses are sent to a group of hosts. Anycast addresses are routed to the nearest receiver from a group of hosts.

What is NAT-PT? a. Network Address Translation-Port Translation. Translates RFC 1918 addresses to public IPv4 addresses. b. Network Addressable Transparent-Port Translation. Translates network addresses to ports. c. Network Address Translation-Protocol Translation. Translates between IPv4 and IPv6 addresses. d. Next Address Translation-Port Translation.

C. NAT-PT translates between IPv4 and IPv6 addresses

Which strategy would be most flexible for a corporation with the following characteristics? -2,400,000 hosts -11,000 routers -Internet connectivity -High volume of traffic with customers and business partners a. Deploy NAT-PT between business and Internet networks. b. Hosts run IPv4 and routers run native IPv6. c. Both hosts and routers run dual stack. d. Enable anycast in the routing protocol. e. Redistribute between the IPv4 and IPv6 networks.

C. Running dual-stack IPv4 and IPv6 on hosts and routers allows for full flexibility for communications for the corporation internally, with partners, and with the Internet.

Select the statement that is true about IPv6 address assignment. a. Configure devices manually using IPv6 address assignment. b. Configure servers using SLAAC. c. Use SLAAC to assign IPv6 addresses and then DHCPv6 to assign additional information to hosts. d. You cannot use DHCPv6 after a host is assigned an IPv6 via SLAAC.

C. SLAAC is used first to assign the IPv6 address and then DHCPv6 is used to assign additional options.

Which protocol maps names to IPv6 addresses? a. Address Resolution Protocol (ARP) b. Network Discovery (ND) c. Domain Name System (DNS) d. DNSv2

C. The DNS maps fully qualified domain names to IPv6 addresses using (AAAA) records.

What is the length of the IPv6 header? a. 20 bytes b. 30 bytes c. 40 bytes d. 128 bytes

C. The IPv6 header is 40 bytes in length.

What address type is the IPv6 address FE80::300:34BC:123F:1010? a. Aggregatable global b. Unique-local c. Link-local d. Multicast

C. The defining first hexadecimal digits for link-local addresses are FE8.

An organization uses an IPv6 address range that it received from its ISP. The IPv6 addresses will be used internally, and employees will access the Internet using Port Address Translation. What is required for DNS? a. DNS servers need to support only IPv4 addresses. b. DNS servers need to support only IPv6 addresses. c. No changes are needed to the DNS servers. d. DNS servers need to support both IPv4 and IPv6 addresses. e. Additional DNS servers for IPv6 addresses are needed. f. DNS servers are not needed for PAT.

D

What changed from IPv4 header to the IPv6? a. Protocol Type became the Next Header field. b. ND is used rather than ARP. c. AAAA records are used rather than A records. d. All of these answers are correct.

D

Which of the following is/are true about IPv6 and IPv4 headers? a. The IPv6 header is of fixed length, and the Next Header field describes the upper-layer protocol. b. The IPv4 header is of variable length, and the Protocol field describes the upperlayer protocol. c. The IPv6 header is of fixed length, and the Protocol field describes the upperlayer protocol. d. A and B e. B and C

D

Which strategy allows both IPv4 and IPv6 addressing/stacks to coexist on a host to facilitate a migration? a. Deploy NAT-PT between the networks. b. Hosts run IPv4 and routers run native IPv6. c. Enable anycast in the routing protocol. d. Run both IPv4 and IPv6 address stacks on devices. e. Redistribute between the IPv4 and IPv6 networks.

D

Which tunneling protocol allows dual-stack hosts to tunnel over IPv4 network that is not multicast enabled? a. 6to4 b. 6over4 c. IPsec d. ISATAP

D

Which of the following is true about fragmentation? a. Routers between source and destination hosts can fragment IPv4 and IPv6 packets. b. Routers between source and destination hosts cannot fragment IPv4 and IPv6 packets. c. Routers between source and destination hosts can fragment IPv6 packets only. IPv4 packets cannot be fragmented. d. Routers between source and destination hosts can fragment IPv4 packets only. IPv6 packets cannot be fragmented.

D. IPv4 packets can be fragmented by the sending host and routers. IPv6 packets are fragmented by the sending host only.

What are three scope types of IPv6 addresses? a. Unicast, multicast, broadcast b. Unicast, anycast, broadcast c. Unicast, multicast, endcast d. Unicast, anycast, multicast

D. IPv6 addresses can be unicast, anycast, or multicast.

What type of address begins with the following prefix? FC00::/7 a. Local-link b. Broadcast c. Multicast d. Unique local unicast

D. Unique local unicast IPv6 addresses use the FC00::/7 prefix.

IPv6 link-local addresses begin with what hexadecimal prefix?

FE8/10.

What type of IPv6 address is the following? FF01:0:0:0:0:0:0:2

It is a multicast address. All IPv6 multicast addresses begin with hexadecimal FF.

True or false: The IPv6 address 2001:0:0:1234:0:0:0:abcd can be represented as 2001::1234:0:0:0:abcd and 2001:0:0:1234::abcd.

True. Both compressed representations are valid.

List the eight fields of the IPv6 header.

Version, Traffic Class, Flow Label, Payload Length, Next Header, Hop Limit, IPv6 Source Address, and IPv6 Destination Address.