Internet of the future

Question 1

Explain the advantages of IPv6 when compared to IPv4.

Answer 1

bigger (128) bit (not 32 bit) address space
new header format that simplifies routing
built in security protocols
capable of auto configuration

Question 2

Distinguish between compatible and mapped addresses and explain their applications.

Answer 2

A compatible address is an address of 96 bits of 0s followed by 32 bits of an IPv4 address. A
mapped address is an address of 80 bits of 0s followed by 16 bits of 1s and followed by 32 bits of
an IPv4 address. A compatible address is used when a computer using IPv6 wants to send a packet
to another computer using IPv6. A mapped address is used when a computer using IPv6 wants to
send a packet to a computer still using IPv4.

Question 3

List three protocols in IPv4 network layer that are combined into a single protocol in IPv6.

Answer 3

Three protocols IGMP (Internet Group Management Protocol – used in Multicasting), ICMPv4
(Internet Control Message Protocol), and ARP (Address Resolution Protocol) in IPv4 combined
into a single protocol, ICMPv6

Question 4

If you are assigned an IPv6 address by your ISP for your personal computer at home, what should be the first (leftmost) three bits of this address?

Answer 4

Global unicast so 001

Question 5

What is the size of the global Unicast Address space?

Answer 5

2^(128-3) = 2^(125)

Question 6

Explain the benefit of autoconfiguration.

Answer 6

Autoconfiguration allows the DHCP to automatically allocate an IP address to a host when the host
joins the network.

Question 7

Explain the benefit of renumbering

Answer 7

Renumbering allows a site to have two prefixes during a transition from one ISP to another. This
will be possible if the DNS protocol also changes

Question 8

Show the unabbreviated colon hex notation for the following IPv6 addresses:
a. An address with 64 0s followed by 32 two-bit (01)s

Answer 8

0000:0000:0000:0000:5555:5555:5555:5555 (::5555:5555:5555:5555)

Question 9

Show the unabbreviated colon hex notation for the following IPv6 addresses:
An address with 64 0s followed by 32 two-bit (10)s.

Answer 9

0000:0000:0000:0000:aaaa:aaaa:aaaa:aaaa (::aaaa:aaaa:aaaa:aaaa)

Question 10

Decompress the following addresses and show the complete unabbreviated IPv6 address:
a. ::2222

Answer 10

0000:0000:0000:0000:0000:0000:0000:2222

Question 11

Decompress the following addresses and show the complete unabbreviated IPv6 address:
1111::

Answer 11

1111:0000:0000:0000:0000:0000:0000:0000

Question 12

Decompress the following addresses and show the complete unabbreviated IPv6 address:
b:a:cc::1234:a

Answer 12

000b:000a:00cc:0000:0000:0000:1234:000a