13 - Questions - IPv6
What are four problems with IPv4 addressing workarounds? (Choose four.)
NAT breaks the end-to-end model of IP. NAT inhibits end-to-end network security. Some applications are not NAT-friendly. The merging of private networks is difficult if overlapping IPv4 address ranges are used.
Which field determines the type of information that follows the basic IPv6 header?
Next Header
How does the MAC address 00a1-6789-abcd translate into the right-most 64 bits of the IPv6 address when EUI-64 is used?
02a1:67ff:fe89:abcd
Which three options are valid representations of the IPv6 address 2001:db8:2bc5:0000:0000:087c:0000:000a? (Choose three.)
2001:db8:2bc5::87c:0:a 2001:db8:2bc5::087c:0000:000a 2001:db8:2bc5:0:0:87c::a
What is the corresponding MAC address for the solicited node multicast address ff02:0000:0000:0000:0000:0001:ff17:fc0f?
33-33-ff-17-fc-0f
Which three mechanisms are used to extend the lifetime and usefulness of IPv4? (Choose three.)
CIDR VLSM NAT
Which two ICMPv6 types are used for testing IPv6 reachability? (Choose two.)
ICMPv6 type 128 ICMPv6 type 129
Which address type is not supported in IPv6?
broadcast
What is the range for IPv6 link-local addresses?
fe80::/10
What is the range for IPv6 multicast addresses?
ff00::/8
You want to ping the loopback address of your IPv6 local host. Which command will you enter?
The correct answer is "ping ::1." The loopback address with IPv4 is 127.0.0.1. With IPv6, that address is "::1."
Which command verifies end-to-end transport layer connectivity for HTTP from a PC over an IPv6 path?
telnet [IPv6_address] 80
What are four benefits of IPv6 over IPv4? (Choose four.)
larger address space simpler header mobility transition richness
Which two ICMPv6 types are used for neighbor discovery? (Choose two.)
ICMPv6 Type 135 ICMPv6 Type 136
Which statement is correct about the EUI-64 address format of the interface ID for stateless autoconfiguration that is used by Cisco?
It expands the 48-bit MAC address to 64 bits by inserting FFFE into the middle 16 bits and then inverting the 7th bit in the first octet.
Which protocol in IPv4 performs the same functions as neighbor discovery in IPv6?
The correct answer is "ARP." Neighbor discovery is a process that determines the data link layer address of a neighbor on the same link, like ARP does in IPv4. Neighbor discovery is used on-link for router solicitation and advertisement, for neighbor solicitation and advertisement, and for the redirection of nodes to the best gateway.
Which new field has a length of 20 bits and is used to mark individual traffic flows with unique values?
The correct answer is "Flow Label." Flow Label is a new field with a length of 20 bits and is used to mark individual traffic flows with unique values. Routers are expected to apply an identical QoS treatment to each packet in a flow.
Which feature does IPv6 support for securely connecting to networks?
The correct answer is "IPsec." IPv6 uses IPsec for securely connecting over the internet. IPsec is mandatory in IPv6, making the IPv6 internet more secure.
In which mechanism can a device be configured with a private IPv4 address but communicate on the internet using a globally routable IPv4 address?
The correct answer is "NAT." NAT breaks the end-to-end model of IP. NAT introduced a model in which a device that is facing outward to the internet has a globally routable IPv4 address, while the internal network is configured with private addresses. These private addresses can never leave the site, so they can be identical in many different enterprise networks.
What is the solicited-node multicast IPv6 address for 2001:db8:1001:f:2c0:10ff:fe17:fc0f?
ff02:0000:0000:0000:0000:0001:ff17:fc0f
In which type of IPv6 address does the sender send the traffic to the nearest of multiple nodes, all of which behave in the same way as other nodes that are identified by the same destination address?
The correct answer is "anycast." An IPv6 anycast address is assigned to an interface on more than one node. All nodes that share the same address should behave the same way so that the service is offered similarly, regardless of the node that services the request.
Which three statements about assigning IPv6 addresses to hosts are accurate? (Choose three.)
The correct answers are "The host identifier portion of the address can be computed automatically using the EUI-64 interface ID," "A node on a link can automatically configure its entire global IPv6 address by appending its interface identifier to a prefix that it learns from a router advertisement message," and "Stateful DHCPv6 keeps a record of which addresses are assigned to which hosts." The methods to assign an IPv6 address to a device are static assignment using a manual interface ID or an EUI-64 interface ID, SLAAC (that can be enhanced with stateless DHCPv6), and stateful DHCPv6.
Which two statements describe the characteristics of IPv6 unicast addressing? (Choose two.)
The correct answers are "global addresses start with 2000::/3" and "There is only one loopback address and it is ::1." Global addresses start with 2000::/3, link-locals start with fe80::/10, loopback is ::1, and an unspecified address is just two colons (::). Each interface will have a loopback address automatically configured.
Which two commands can you use on a Cisco network device to test and troubleshoot IPv6 connectivity? (Choose two.)
The correct answers are "ping" and "traceroute." You can use several verification tools to verify end-to-end IPv6 connectivity. A successful ping means that the device endpoints are able to communicate. This result does not mean that there are no problems, it simply proves that the basic IP connectivity is working. You can also use the traceroute command. The results of the traceroute command can help you determine how far along the path data can successfully reach. Knowing at what point the data fails can help you determine where the issue is.
Which Cisco IOS interface command assigns a static IPv6 address using an EUI-64 interface ID?
ipv6 address 2001:0db8:0:1::/64 eui-64
Which Cisco IOS global configuration command is needed to enable IPv6 routing on routers?
ipv6 unicast-routing
Which address bits uniquely identify a group ID in the IPv6 multicast address?
The correct answer is "last 112 bits." An IPv6 multicast address defines a group of devices known as a multicast group. All IPv6 multicast addresses use the prefix ff00::/8. The 8-bit prefix is followed by 4 bits allocated for flags and a 4-bit scope field, which defines the range to which routers can forward the multicast packet. The remaining 112 bits represent the group ID and identify the packet destinations. Some common group ID values are ::1, identifying all IPv6 devices within the scope, or ::2, which identifies all IPv6 routers within the scope.
