Chapter 9 - IPv6 Flashcards
Since IPv6 does not use broadcasts, how do IPv6 devices discover routers on the network?
Neighbor Discovery Protocol (NDP)
- NDP uses the IPv6 version of ICMP
How many bits is a iPv6 address
128 bits
How is an IPv6 address laid out?
8 groups of 4 hex characters, separated by colons :
xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
What are the rules for abbreviating a IPv6 address?
- The :: (double colon) can be only used once, and can remove consecutive groups of zeros.
- Preceeding zeros in an octet can be omitted (example- “00B0” reduces to “B0”)
- An octet of all zeros can be reduced to just 0 (example- 1234:0000:ABCD reduces to 1234:0:ABCD)
What is the modified EUI-64 format?
This is used to construct the host ID of a Link Local addresses by combining the following:
- the Physical MAC address
- Inserting FFFE into the middle of the MAC address
- Modifies the 7th digit (from the left in the original MAC address) to the inverse. if it is a 0 it is turned into a 1 and vice versa.
What does a loopback address look like in IPv6?
::1
What does an IPv6 all-node multicast addresses look like?
Always starts with FFXX:
X’s are some other hex number.
FF02 is a link local in scope.
For example FF02::1
In IPv4 this was 224.0.0.1
What is the “all routers” IPv6 multicast address?
FF02::2
In IPv4 it was 224.0.0.2
What does a Global IPv6 Unicast address start with?
2000 to 3FFF
these are usually assigned by ISP’s. They are able to be routed through the Internet.
What is an IPv6 anycast address?
An anycast address is an address that is assigned to a set of interfaces that typically belong to different nodes. A packet sent to an anycast address is delivered to the closest interface identified by the anycast address.
- Think of this as One to “Closest”
You really can’t tell the difference between a unicast address and an anycast address, in that assigning the SAME unicast address to several nodes or interfaces makes it an anycast address.
- Nodes to which the anycast address is assigned must be explicitly configured to recognize that the address is an anycast address.
What is the IPv6 multicast address for RIPng?
FF02::9
In IPv4 this was 224.0.0.9
What does a solicited-node multicast address look like?
FF02::1:FFXX:XXXX
The X characters are the last 24 bits of the host ID
Which two features can be used to protect against rogue IPv6 devices?
SEND - Secure Neighbor Discovery
RA Guard - Router Advertisement guard)
What command needs to be issued in order for a router to send packets through an IPv6 network on behalf of clients?
(config)# ipv6 unicast-routing
What extra step / command needs to be issued so that EIGRP will route IPv6 packets on a router?
(config)# ipv6 unicast-routing
