Chapter 13 - IPv6 Flashcards
How long is a IPv6 address and how many possiblities are there?
Ipv6 is a 128-bit address allowing up to 2^128 (3.4x10^38) addresses.
What is one advantage of IPv6
IPSec is a standard part of every IPv6 stack meaning every packet sent from a NIC is encrypted. Also provides more efficient routing scheme by using aggregation
Give an example of an IPv6 address and explain the structure
2001: 0000:0000:3210:0800:200C:00CF:1234
- Quartet/Hextet = each group of numbers
- Numbers between 0000:FFFF
- Eight groups of 4 characters
IPv6 addresses can be hard to read, what is a way to simplify them?
Leading zeroes can be shortened to '::' 2001:0000:0000:3210:0800:200C:00CF:1234 now becomes 2001:0:0:3210:800:200C:CF:1234 and can now become 2001::3210:800:200C:CF:1234 NOTE: '::' can only be used to represent the zeroes once FEDC:0000:0000:0000:00CF:0000:BA98:1234 becomes FEDC::CF:0:BA98:1234
What is the IPv6 loopback address
::1
How does one determine an IPv6 address is link-local
The first 64 bits will start with FE80::/10 followed by 54 zero bits.
FE80:0000:0000:0000
The second 64 bits are the ‘Interface Identifier’ and is generated by either
- Systems post-vista or OSX, and linux will generate a random number
- Legacy systems like XP will use the MAC
How does subnetting happen in IPv6 and who passes them out?
Because the last 64 bits are generated by the NIC, the subnet mask is a maximum /64
IANA passes out /48 subnets to big ISPs, and /16 for smaller ISPs who will then pass out /64 subnets
Define unicast address (IPv6)
This is the systems link-local address
Define Multicast address (IPv6)
a set of reserved addresses designed to go only to certain systems. Individual addresses are assigned to specific applications.
What address is used to encapsulate IPv6 multicast packets
33-33-xx-xx-xx-xx
What is the function of the address FF02::1
All nodes address
Waht is the function of the address FF02::2
All routers address
What is the function of the address FF02::1:FFxx:xxxx
Solicited-Node Address
Where does a DNS server keep the IP addresses of the root servers
Root Hints file
Define ‘Anycasting’
Starts by giving a number of computers the same IP address. Routers use BGP to determine which computer or cluster is closest. The router then send the packet to the closest root DNS server.
How does a system get on the internet with IPv6
It needs a Global Unicast address and is only given out by the default gateway
Explain the process, in detail, of getting a Global Unicast Address
- Computer sends out a solicitation message on boot
- IPv6 Router sends prefix to computer
- Computer adds interface identifier or EUI64 to prefix
4.
Define prefix delegation
tells the router to go upstream and get a prefix to hand out to clients
Define no-default routers
tier-one routers that connect to other tier one routers. They can not have a default route
Define aggregation
Every router underneath one router uses a subset of that routers existing routes.
Give the formula for a IPv6 address
48 bit from upstream router + 16-bit from default gateway + 64 bit unique number
What are the two modes that DHCPv6 uses?
Stateful - passes out IPv6 addresses, subnet masks, and defualt gateways, DNS, and TFTP server addresses.
Stateless - passes out only optional information (default)
How does a DNS server store a IPv6 record
Storing it in a record type of AAAA
Define 4 to 6 tunnel
encapsulating IPv6 traffic into a IPv4 tunnel
Define 6 to 4 tunnel
Enables IPv6 traffic to use the IPv4 internet. Generally used to connect two routers.
- Always start with 2002::/16
- 192.88.99.1 is the 6to4 anycast address
Define 6in4
one of two tunneling protocols that can go through a NAT
Define Teredo
IPv6 tunneling protocol
Start with 2001:0000:/32
Built into windows
Define Miredo
Open source version of Teredo for linux
Define Intra-site automatic tunnel addressing protocol
ISATAP
Designed to work within an IPv4 network by adding IPv4 address to an IPv6 prefix.
ex. 2004:DB8::98CA:200:131.107.28.9
What is TSP and TIC
Tunnel Setup Protocol and Tunnel Information and Control are used to take advantage of automatic configuration
Define Overlay tunnel
enables two IPv6 netowrks to connect over an existing IPv4 infrastructure
What ius a manual tunnel used for
Creates a simple point to point connectionbetween the two IPv6 networks
How does a IPv6 multicast fiffer from broadcasts
Both broadcasts and multicasts are sent to all network nodes but in multicast only the destination nodes process the incoming packets
