Week 6 - IPv6 Addresses* Flashcards
How many bits is an IPv6 address?
128 bits
How is an IPv6 address split up? How many bits per?
IPv6 is split into 8 groups of 4 hexadecimal numbers, 16 bits each group
What IPv6 addresses are reserved for education, documentation, books and courses?
Every address that starts with 2001:0db8
How are IPv6 addresses broken down smaller? 2
IPv6 is broken down more by:
1. Removing any leading 0’s from a group
2. Any consecutive groups composed of just 0’s can be replaced with 2 colons (Can be done only ONCE)
For example: :0:0:0: = ::
What are link-local unicast addresses? How is it configured?
Link-Local Unicast Addresses are configured based on the host’s MAC address allowing local segment communication
Link-local addresses are used by ____ to receive their _____?
Link-Local Addresses are used by an IPv6 host to receive its network configuration
(Link-Local Addresses provide network configuration to an IPv6 host)
What are the 9-10 fields of an IPv6 header?
- Version
- Traffic Class (different priorities for different classes)
- Flow Label - QoS used with Traffic Class
- Payload Length
- Next Header - unique to IPv6 - can chain headers
- Hop Limit - TTL
- Source Address
- Destination Address
- Optional Header mentioned
- Data Payload
Why can’t we switch to IPv6 all at once?
There are too many devices running IPv4, legacy devices, costly to upgrade infrastructure
What is IPv4 mapped address space in terms of IPv6?
These are addresses that can be directly correlated to an IPv4 address
What are IPv6 tunnels in relation to IPv4?
IPv6 tunnel servers take incoming IPv6 data, encapsulate it into an IPv4 datagram, and send it to the other IPv6 tunnel to be de-encapsulated
(Tunnels are IPv6 tunnel servers on either endpoint)
What is an IPv6 tunnel broker?
Provides the IPv6 tunnel servers (endpoints) so you don’t have to buy them
How do you correlate an IPv6 address to an IPv4?
When you see an IPv6 address that begins with 80 0’s and 16 1’s, it’s part of the iPv4 mapped address space.
Last 32 bits are the IPv4 address it’s meant to represent
How does a Host’s MAC address change when configured to a link-local unicast address? Where is it inserted after? (IPv6)
Host’s MAC address is run through an algorithm so its 48-bit number turns into a unique 64-bit number and is inserted into the address’s Host ID
What is the IPv6 loopback address before it’s broken down?
31 0’s with a 1 at the end
What does an IPv6 loopback address look like after it’s broken down?
::1
