CCNA 1.8 and .9 - IPv6 Flashcards
What is the IPv6 equivalent of ARP?
Neighbor Discovery Protocol (NDP)
In IPv6, what is the difference between a global unicast and unique local address?
Global unicast are unique throughout the world, like a public IPv4 address is. Unique local is similar to using the private address ranges in IPv4 - they need to be NATted before accessing the global internet.
IPv6 unique local addresses start with…
FD
IPv6 multicast addresses begin with…
FF
IPv6 link local addresses begin with…
FE80
What IPv6 multicast address is used to send packets only to other IPv6 routers on the local link?
FF02::2
What command enables IPv6 routing globally on the router?
ipv6 unicast-routing
What are the EUI-64 steps for creating an address?
1) take the MAC address and split it in half
2) add “FFFE” in the middle
3) flip the seventh bit
What is SLAAC?
Stateless Address Autoconfiguration
What command enables SLAAC on an interface?
ipv6 address autoconfig
What do IPv6 link-local addresses do and not do?
They do not carry user data. They are used for overhead protocols and routing. They are not advertised from one router to another subnet. e.g. NDP, next-hop addresses
What is the prefix of an IPv6 link-local address?
FE80::/10
True or false: when the global unicast ipv6 address is configured on an interface, the link-local address is also generated automatically.
True
What are the four ways of configuring an IPv6 address on an interface?
1) ipv6 address <address/prefix-length>
2) ipv6 address <prefix/prefix-length> eui-64
3) ipv6 address autoconfig (SLAAC, uses eui-64)
4) ipv6 address dhcp (learns entire address without eui-64)
What is the purpose of the “ipv6 enable” command?
It is used on point-to-point WAN links where a global unicast address simply isn’t necessary. It enables a link-local address for the purposes of routing packets, and that’s all.
What is the reserved range for IPv6 multicast addresses?
FF30::/12
List the uses for the following IPv6 multicast addresses:
1) FF02::1
2) FF02::2
3) FF02::5 and ::6
4) FF02::9
5) FF02::A
6) FF02::1:2
1) All IPv6 hosts on a link
2) All IPv6 router interfaces on a link
3) OSPFv3 routers (5) and DRs (6)
4) RIPng
5) EIGRPv6
6) DHCPv6 relay agent
What are the five IPv6 multicast scopes?
1) FF01, interface-local, traffic from one process to another within the router
2) FF02, link-local, from one router to another, not forwarded beyond that
3) FF05, site-local, can be forwarded between routers but not over WAN links
4) FF08, organization-local, for an entire company
5) FF0E, no boundaries
What is the “unspecified” IPv6 address?
:: (all 0s)
What is the IPv6 loopback address?
::1 (127 binary 0s followed by a 1)
How would you describe IPv6 “anycast”?
A host needs a service, it makes a request for that service, the router picks up the request and forwards it to the nearest router that provides that service.
What prefix length is often used for an IPv6 anycast address?
/128 (host address)
What are four functions of NDP?
1) Neighbor MAC discovery
2) Router discovery
3) SLAAC
4) Duplicate address detection (DAD)
What are NS and NA messages?
NS = neighbor solicitation, asking for their MAC address
NA = neighbor advertisement, the reply with the MAC address
What are the three steps in SLAAC?
1) Host sends RS to learn the local subnet prefix
2) Host builds an address using EUI-64 or a random address
3) Host uses DAD to verify the address’s uniqueness
True or false: An IPv6 host configured statically or via DHCP will still use DAD.
True
If you want to use eui-64 calculation in your IPv6 address, you still need to give what info to the interface?
The prefix and length
True or false: IPv6 static routes can use an outgoing interface as the next hop.
Partially true, partially false - you can use an interface on a serial interface, but not an ethernet interface.
What are the three options for specifying the next hop when configuring an IPv6 static route?
1) GUA/ULA
2) outgoing interface + GUA/ULA
3) outgoing interface + LLA
