Comptia Net + Chapter 12 IPv6

What is Nat64?

- A transition mechanism that embeds IPv4 packets into IPv6 packets for network traversal - Typically you have a NAT64 gateway that handles the traffic between the IPv4 and IPv6 segments doing the address translation on the fl, and keeping track of who's who on either end.

6in4 tunneling

-An IPv6 tunneling standard that can go through IPv4 Network Address Translation(NAT) - One of the most popular IPv6 tunneling standards

What is Neighbor discovery Protocol (NDP)?

-IPv6 protocol that enables hosts to configure automatically their own IPv6 addresses and get configuration information like routers and DNS

Is Nat needed with IPv6? Why or Why not?

-No. -Because of the massive side of the IPv6 address space

What is DHCPv6?

-The version of DHCP used with IPv6. Uses port number 546 for client to server communications and port number 547 for server-to-client communications. - Works like traditional DHCP in that you have to configure a DHCPv6 server and client

What rules apply to prefixes in IPv6?

-no more 64 bits /64 -the 5 RIR pass out /48 prefixes to big ISP and end users that need large allotments ISPs and other will borrow the other /16 bits for subnetting then pass out /64 interface IDs to end users -link local adddress uses a prefix lenght of /64

The hexadecimal number range for IPv6 address?

0000 to ffff

Which of the following operating systems have Teredo built in? (pick 2) 1. Windows 7 2. mac0S 3. Windows 10 4. Linux

1 and 3. Teredo is built into windows

Which of the following is a valid IPv6 address? 1. 2001:bead:beef::1 2. 2001:30f5::3d62::04ffe 3. 192.168.1.4:ff45:129g:48fd:1 4. 2001.0470.b33e.23f4.27de.d34a.aed2.18217

1. 2001:bead:beef::1

What two critical parts of the internet have been made ready for IPv6?

1. All root DNS servers support IPv6 2. Almost all Tier 1 ISP routers properly forward IPv6 packets

What two components make up the Network Prefix portion of an IPv6 address?

1. Global routing prefix 2. Subnet ID

What are the five packet types of the Neighbor discovery Protocol (NDP)?

1. Neighbor solicitation 2. Neighbor advertisement 3. Route solicitation 4. Router advertisement 5. Redirect

What are two ways to abbreviate IPv6 addresses?

1. Omit leading zeros (00cf becomes cf and 0000 becomes 0) 2. Replace one or more 16 bit groups of all zeros with double colons (only used once)

What are the two modes that a DHCP server works in?

1. Stateful 2. Stateless

What is the name of the two general sections of an IPv6 address? what are they used for?

1. The network Prefix - first 64 bits, used for routing 2. Interface ID - the second 64 bits, the user address

What are the two automatic configuration protocols that the tunnel brokers like to take advantage of?

1. Tunnel Setup Protocol (TSP) 2. Tunnel Information and Control (TIC) protocol

What Three types of Addressing does IPv6 perform

1. Unicast address 2. Multicast 3. anycast

How does a system get assigned a Global unicast address?

1. upon boot up the the host sends out a router solicitation message on multicast address ff02::2 2. Router responds to message with a router advertisement advising of prefix 3. computer generates the rest of the global unicast address, the remaining 64 bits

How does an Overlay tunnel work?

1.The routers that connect the IPv6 networks are dual stacked (running IPv6 and IPv4). 2. The IPv6 packets are encapsulated in an IPv4 packet, and travel over the infrastructure to the router at the other end of the tunnel which strips off the IPv4 packet and sends the remaining Ipv6 packet on its way.

How many bits are IPv6 addresses?

128

How many bits is the subnet ID for the LAN in a IPv6 network?

16 bits.

Which choice is not a valid representation of the IPv6 address: 2001:C2A:0000:0000:BB29:0000:3F00:A5B6? 1. 2001:0C2A::BB29:0000:3F00:A5B6 2. 2001:C2A::BB29::3F000:A5B6 3. 2001:0C2A:0000:0000:BB29:0000:3F00:A5B6 4. 2001:0C2A:0000:0000:BB29::3F00:A5B6

2. 2001:C2A::BB29::3F000:A5B6

What is the /48 prefix of the address 2001:0480:b6f3:0001::001?

2001:480:b6f3

What is the 16 prefix for all 6to4 address?

2002

Which statement is not true of IPv6 addresses? 1. Outbound IPv6 addresses are randomized by the operating system 2. EUI-64 can be traced back to the source computer 3. IPv4 and IPv6 are automatically translated back and forth as required 4. There are no private IPv6 addresses

3. IPv4 and IPv6 are automatically translated back and forth as required

Which of the following is not a characteristic of an IPv6 address? 1. 128 bits 2. written with hexadecimal characters 3. groups are separated by dashes 4. Broken up into eight groups.

3. groups are separated by dashes

What is the formula for a IPv6 IP?

48-bit prefix from upstream router + 16 bit subnet ID from default gateway + 64 bit interface ID = 128bit IPv6 address

What is the RIR? What is their role with IPv6?

5 regional internet registries, they pass out IPv6 prefixes

What are the two types of NAT Traversal IPv6 tunneling protocols?

6in4 teredo these protocols are capable of going through IPv4 Nat

How are IPv6 addresses written?

8 groups of four hexidecimal, using a colon as a separator

What is the IPv6 loop back address in Short hand? In Long hand?

::1 0000:0000:0000:0000:0000:0000:0000:0001

What is Teredo tunneling? What does its address's start with?

A NAT-Traversal IPv6 tunneling protocol, built into windows Teredo addresses start with 2001:0000:/32

What does a client need to access IPv6 content on the internet?

A global unicast address

Router Advertisement (RA)

A message defined by the IPv6 Neighbor Discovery Protocol (NDP), used by routers to announce their willingness to act as an IPv6 router on a link. These can be sent in response to a previously received NDP Router Solicitation (RS) message.

Router Solicitation (RS)

A message defined by the IPv6 Neighbor Discovery Protocol (NDP), used to ask any routers on the link to reply, identifying the router, plus other configuration settings (prefixes and prefix lengths). LAN ID

Neighbor Advertisement (NA)

A message defined by the IPv6 Neighbor Discovery Protocol (NDP), used to declare to other neighbors a host's MAC address. Sometimes sent in response to a previously received NDP Neighbor Solicitation (NS) message.

What is "anycast" ?

A method of addressing groups of computers as though they were a single computer. Anycasting starts by giving a number of computers (or clusters of computers) the same IP address. Advanced routers then send incoming packets to the closest of the computers.

What is a neighbor solicitation (NS)

A multicast message defined by the IPv6 Neighbor Discovery Protocol (NDP), used to ask a neighbor to reply with a Neighbor Advertisement, which lists the neighbor's MAC address.

What is a aggregation?

A router hierarchy in which every router underneath a higher router always uses a subnet of that router's existing routes.

What is a router advertisement?

A router's response to a client's router solicitation, also sent at regular intervals, that gives the client information to configure itself. (prefix, prefix length, etc)

What is a global Unicast address?

A second IPv6 address that every system needs to in order to get on the internet. IT is passed out from the default gateway.

What is a multicast address?

A set of reserved addresses designed to go from one system to any system using one of the reserved addresses.

What is a unicast address?

A unique IP address that is exclusive to a single system. Typically refers to a single sender or a single receiver, although it can be used in both sending and receiving.

What service do tunnel brokers provide?

A way for users to jump the gap between their computers and the IPv6 internet routers.

What Kind of DNS records to IPv6 address use?

AAAA (four times a normal A record)

When setting up an IPv6 server, you have to set up a record type of _______.

AAAA. Chosen because its 4x the length of IPv4 address.

What is Miredo?

AN open source implementation of teredo for linux and some other Unix-Based systems. It is a NAt-traversal IPv6 tunneling protocol .

2000::/3 address type?

Aggregatable global unicast

In an IPv6 environment, what happens if an upstream router changes the prefix that is sent downstream?

All down stream routers make an "all nodes" multicast and all clients get new IP addresses, this keeps aggregation intact.

Multicast address FF02::1 ?

All nodes address

Multicast address FF02::2

All routers address

What is prefix delegation?

An IPv6 router configuration that enables it to request an IPv6 address block from an upstream source, then disseminate it to local clients.

What is ISATAP?

An IPv6 tunneling protocol that adds the IPv4 Address to an IPv6 prefix. -designed to work within an IPv5 network by adding the Ipv5 address to an Ipv6 prefix to create a nonstandard address for the endpoints.

6to4 tunneling

An IPv6 tunneling protocol that doesn't require a tunnel broker. It is generally used to directly connect two routers because it normally requires a public IPv4. Not used.

Why do we need IPv6?

Because when IPv4 was created there were only 4 billion addresses and now we have more devices than addresses.

What must a computer be to be able to read a particular multicast?

Configured to be a member of the particular group receiving a multicast.

What is a manual tunnel?

Creates a simple point-to-point connection between the two IPv6 networks.

Which of the following is the valid reduced version of the address 2001:0489:000f:0000:0000:1f00:0000:000d A. 2001:489:f::1f:0:d B. 2001:489:f::1f00::d C. 20001:0489:000f::1f00:0000:000d D. 2001:489:f::1

D. 2001:489:f::1f00:0:d leading zeroes can be dropped and only one group of contiguous zeroes can be represented by a double colon.

Stateless DHCPv6

Describes a DHCPv6 server that only passes out information like DNS servers' IP addresses, but doesn't give clients IPv6 addresses.

What is Stateful DHCPv6

Describes a DHCPv6 server that works very similarly to an IPv5 DHCP server, passing out IPv6 addresses, subnet masks, and default gateways as well as optional items like DNS server addresses.

What are benefits of aggregation in routing?

Drastically reduce the size and complexity of routing tables and could make the internet faster give a more detailed, geographic picture of how the internet is organized not able to implement in IPv4, part and parcel for IPv6

True or False: DHCP is required to receive an IPv6 address automatically. Why?

False Router advertisements allow clients to receive a valid IPv6 address without a DHCP server

What are the first 64 bits of a link-local address?

Fe80::/64 fe80:0000:0000:0000:

What do computers running IPv6 have to have to access the internet?

Global unicast address.

What is a scenario that you would need DHCP in a IPv6 networking situation?

If you want all your users to run on a local DNS server rather than one from your ISP.

What are Tunnel Brokers?

In IPv6, a server that creates the actual tunnel and (usually) offers a custom-made endpoint client for you to use, although more advanced users can often make a manual connection.

What is the proper name for the host portion of an IPv6 address?

Interface ID

What is 4to6?

Internet connectivity technology that encapsulates IPv4 traffic into an IPv6 tunnel to get to an Ipv6-capable router - works like any other tunnel, encapsulating one type of data into another. Requires a tunnel client to be downloaded and ran.

What does ISATAP stand for?

Intra-Site Tunnel Addressing Protocol.

What is the purpose of an Overlay tunnel?

It enables two IPv6 networks to connect over an existing IPv4 infrastructure such as the internet

FE80::/10 address type?

Link local unicast

Local routers still need a WAN address with IPv6, so with out NAT, what do they do?

Listen for router advertisements from upstream routers to provide its WAN IP address, its prefix length, its default gateway and DNS servers - essentially a local router will receive its Global prefix (usually 48 bits) and a unique subnet ID for the lan (usaully 16 bits) creating a unique 64 bi network ID for the lan

do you need DHCP with IPv6?

No

Does every system process a multicast?

No, every system may see the multicast frame, however only the computers specifically set up to process the frame process it. The rest drop the frame at layer 2.

How was the interface Id originally generated? How is it generated now?

On windows XP and windows server 2003 it was generated based off the MAC address to create a 64 bit number called the Extended unique identifier (EUI-64). Do to security this is no longer done now its generated randomly by the NIC

What is Tunnel set up Protocol (TSP)?

One of the protocols that sets up IPv6 tunnels and handles configuration as well as login.

What is Tunnel Information and Control Protocl (TIC)?

One of the protocols that sets up tIPv6 tunnels and handles configuration as well as login.

How many times can you use double colons ( :: ) when shortening the notation of a IPv6 address? Why?

Only once. You would not be able to tell how many sets of zeroes were in each group.

What is a subnet ID?

Portion of an IP address that identifies bits shared by all hosts on that network.

Instead of NAT and private network ID's, what does IPv6 rely on?

Route Advertisements.

All nodes multicasts are pretty much just used by whom?

Routers, not typical traffic

FF02::1:FF00:0/104 address type?

Solicited node multicast

Multicast address FF02::1:ffxx:xxxx

Solicited-node address

What is "prefix length" in IPv6?

The IPv6 term for subnet mask, in most cases its /64

What is the Link-local address for IPv6

The address that a computer running IPv6 gives itself after first booting

What is a Global routing prefix?

The first 48 bits of an IPv6 unicast address, used to get a packet to its destination, or routing.

What IPv6 process is the equivalent to an IPv4 ARP?

The neighbor solicitation and Neighbor advertisement process.

How do systems know where to send IPv6 packets?

They utilize the IPv6 prefex lengths to determine whether to send packets to a local MAC address or to the default gateway to send packets out to the internet.

What two IPv6 tunneling protocols does Windows come with?

Toredo and 6to4

Because there is a gap between our current systems and the top tier for IPv6, what do we have to use to be able to implement an IPv5 to IPv6 transition at home?

We utilize IPv4 to IPv6 tunneling.

Why can't we just say "hey IPv4 is Dead, we are using IPv6.`

While most top tier routers and DNS are ready for IPv6, not every point of connection between the regular users and the top tier have been upgraded to handle IPv6

What is a router solicitation message?

an IPv6 query from a host to find routers and get information to configure itself.

What is a benefit of aggregation working with IPv6?

enables the entire IPv6 network to change IP addresses on-the-fly to keep aggregation working.

Multicast packets are ________ into ethernet frames.

encapsulated

what are Manual tunnels good for?

good for regular, secure (via IPsec) communication between two networks.

IPv6 always uses ___ addressing.

link-local

FF00::/8 address type?

multicast

Does it matter if the letters in hex are upper or lowercase?

no

What are no-default routers?

tier 1 routers that connect to the other Tier 1 routers, do not have a default gateway

IPv6 addresses are generally split into how many sections? how many bits per section?

two 64 bit sections