IT2400 Chapter13

What is a valid IPv6 subnet mask?

/64

Link-local address always use

/64 as the subnet mask

How many bits comprise an IPv6 address?

128

IPv6 supports

2 ^128 (or 3.4 x 10^38) addresses

there are 4 popular tunneling standards

6to4, 6in4, Teredo and ISATAP

Ipv6 replaced broadcasts with multicasts

A multicast is a set of reserved addresses designed to go to only certain systems. Packets sent to addresses beginning with FF02::2 are only sent to routers

As IPv6 clients can get a portion of their IP address from the default gateway server, what purpose does a DHCPv6 server serve?

A) DHCPv6 servers can still distribute DNS server information.

Which of the following IPv6 addresses are equivalent to ACCB:0876:0000:0000:FD87:0000:0000:0064?

ACCB:876::FD87:0:0:64 ACCB:876:0:0:FD87::64

Which of the following is a valid link-local address?

B) FE80::1994:33DD:22CE:769B

Which operating systems fully support IPv6? (Select three.)

B) Windows XP C) Windows Vista D) Macintosh OS X

How do IPv6 multicasts differ from broadcasts?

Both broadcasts and multicasts are sent to all network nodes, but in a multicast, only the destination nodes read the incoming packets.

Which of the following is a valid IPv6 address?

C) 2541:FDC::ACDF:2770:23

What must your computer have to access the IPv6 Internet?

D) A global unicast address

DHCPipv6 servers may be bypassed by manually entering

DNS server information into the IP settings of an ipv6 clinet.

A packet has been sent to the address FF02:0000:0000:0002:0BCD:23DD:3456:0001. What will read the sent packet?

Every router on the network.

A link local address always starts with

FE80::. The last 64 bits of the link-local address are generated from the NIC's Mac address

in addition to IPv6 expanded address space

Ipv6 improves security by supporting IPSec out of the box

What is the main benefit of IPv6 aggregation?

It reduces the size and complexity of routing tables, allowing routers to work more efficiently.

What is true of link-local addresses?

The last 64 bits are always generated from the MAC address, except on Windows Vista and Windows 7.

What is true of current global addresses?

They always begin with 2001::, 2002::, 2003::, and so on.

Microsoft Windows Vista and Windows 7 generate the last 64 bits of a link-local address randomly so as to not reveal the Mac address

This adds security against hackers

IPv4 supports only

about 4 billion addresses which is no longer enough for the future

ISATAP

adds an ipv4 address to an ipv6 prefix. for example, 2001:DB8:98CA:200:131.107.28.9

ipv6 is active by default on Mac OSX

and active by default on most Linux installs using at least kearn2.6

Multicasts, like broadcasts,

are still sent to every computer on the network. Unlike broadcasts, through only the destined systems read the multicast packet

TSP and TIC

are two automatic configuration protocols for setting up IPV4-to-IPV6 tunnels

IPv6 address are composed of 128

bits written in hexadecimal notation. Every 4 bits are separated by a colon. 2001:0000:0000:3210:0800:200C:00CF:1234 is a valid Ipv6 address

Global unicast addresses are distributed

by the default gateway router, provided the router is configured to pass out global Ipv6 addresses

an ipv4-to-ipv6 tunnel

can be used to bridge the gap created by non ipv6 routers, allowing you access to the root and tier-one routers that do support ipv6

only 6in4 are teredo

can go through NAT

The first half of the global unicast address is called the prifix and

consits of the nework ID and subnet mask. The prefix is passed out by the default gateway router. The last half of the global address is self generated by the computer

Do not connect t the ipv6 internet on a

critical computer. limited ipv6 support means potential security risks

Stateful DHCPv6 servers pass out Ipv6 addresses, subnet masks,

default gateway addresses and DNS server addresses as well as other optional information

ipv6 doesn't support NAt.

every ipv6 address is exposed to the internet, use a good firewall.

Currently, all root DNS servers support IPv6 resolution and almost all tire-one ISP routers, properly

forward ipv6 pakcets. However the routers between you and these root and tier-one servers may not support Ipv6 at the moment

Computers using IPv6 that are on the internet

have two IPv6 addresses: a link-local address and a global address.

An Ipv6 computer not on the Internet needs only the self-generated link-local address to participate on a local network.

however, a server n such a network still needs a static IP address, not a random self-generated link-local address.

Stateless DHCPv6 servers pass out only optional

information. Stateless DHCPipv6 servers are preferred to stateful servers because stateless servers support aggregation.

An Ipv6 global unicast address is required for

internet access

Teredo is built

into the windows. Teredo addresses always start with 2001:0000:/32

link local address

is similar to an IPv4 APIPA address in that it is self-generated. the link-local address is guaranteed to be unique because it is partially based on the MAC address of the NIC

6to4

is the dominant tunneling protocol and is the only one that doens't require a tunnel brocker. however, it is the most challenging to set up. 6to4 addresses start with 2002:/16

What is the only type of IPv6 address required to communicate with other computers on a local network?

link-local

Leading zeroes can be dropped and double colons

may be used to represent consecutive groups of zeros in order to write an IPv6 address with fewer characters. 2001::3210:800:200C:CF:1234 is a valid IPv6 address.

IPv6 subnet masks are represented with a /X CIDR

naming convention. FEDC::CF:0:BA98:1234/64 translates to 64-bit subnet mask.

Ipv6 link-local address are unicast

or unique to a specific computer or network node.

Aggregation

reduces the size and complexity of routing tables by allowing downstream routers to use a subset of an upstream router's routes to populate its routing table rather than tens of thousands of disjointed routes

While Ipv6 global addresses are passed out by the default gateway

router (with a portion self generated) DHCP servers are still important because they pass out DNS Server information

IPv6 provides a more efficient

routing scheme because it uses aggregation

it is estimate that ipv4 addresses will run out

somewhere between the year 2011-2019

A tunnel broker is a service provider

that creates the tunnel, acts as the far endpoint, and often provides a tunneling client for easier setup

What type of address applies to a single unique network node?

unicast

Not all versions of windows support ipv6 and some that do enable it by default

whereas others require manual installation