1. 29-03-2011
1
KAMRAN
Roll no. 29
Mcs-II
Batch-IV

2. 2
Overview
1. IPv4 and IPv6
2. Difference b/w IPv4 and IPv6
3. Deficiencies of IPv4
4. Advantages od IPv6
5. Transition from IPv4 to IPv6

3. 3
1. IPv4 and IPv6
IPv4: a mechanism used by TCP/IP
still using today
both are
connectionless
services
IPv6: * newer version.
* deployed in 1999.
* for future use.

4. 4
2. Difference b/w IPv4 and IPv6
S.no IPv4 IPv6
1.Address size 32-bit 128-bit
2.Address format Dotted decimal notation Hexadecimal notation
192.149.252.76 3FFE:F200:AB00:0123:
0234:890A:XC01:SD98:
3.Prefix notation 192.149.0.0/24 3FFE:F200:AB00:0123::/48
32 128
4.No. of Addresses 2 = 4 billions + 2 =340,282,366,920,
938,463,374,607,
431,768,211,456
haeder data area
5.datagram format
1.................N
base extension payload area
header header
6. Headers IPv4 has a 20 octets i.e. IPv6 has 8 fields with a
160 bits, containig info. total size of 40 octets i.e.
essential to routing and 320 bits.
delivery.
it consists of 12 fields

5. 7. Datagram formats:
header data
VER 4 bits HLN 4 bits service type total length 16 bits
8 bits
Identification 16 bits flags 3 bits fragmentation offset 13 bits
time to live 8 bits protocol 8 bits header checksum 16 bits
Source IP address
Destination IP address
Options
32-bits Address
WHILE

6. Format of an IPv6 datagram
VER PRI Flow label
Payload length Next header Hop limit
Source address
Destination address
next header header length
next header header length
next header header length

7. NOW TO COMPARE THE HEADER FORMATS
1. " Header length" is eliminated from IPv6 b/c length is fixed in IPv6
2. "Source type" field is also eliminated . The "priority & flow label" are
together over the service field in IPv6.
3. The "total length" field is eliminated in IPv6 & replaced by "Payload
length".
4. the "Identification, flags, & offset" field are eliminated too. they are
included in the "fragmentation extension header".
5. the "protocol" field is replaced by "Next header" field.
6. "time to live" field are called hop limit in IPv6.
7. The "header checksum" is removed because the checksum are
provided by upper layers & is no need here.
8. the "option" field are implemented as "Extention header" in IPv6.

8. 3. Deficiencies of IPv4
1. subnetting, classless addressing and NAT address depliction is still
long term problems
2. The Internet must accummodate real-time audio, video tx. this type
of tx requires minimum delay strategies and reservation for resourses.
3. The Internet must accummodate encryption and authentication of
data.but this is not provided in IPv4.
NOW
4. Advantages od IPv6
1. larger address space (which has a huge increase in address space)
2. better header format (in which options are separated from base
header) this simplifies speed up the routing process.
3. new options (to allow for additional functionality)
4. Support for high security

9. 5. Transition from IPv4 to IPv6
three strategies
Dual stack Tunneling Header translation

10. dual stack
transport &
app. layers
IPv4 IPv6
underlying
LAN or WAN
technology
to IPv4 system to IPv6 system

11. Tunneling
IPv4 header
IPv6 header
Payload
IPv6 header IPv6 header
tunnel
Payload Payload
int. nodes int. nodes int. nodes IPv6 host
IPv6 host
HEADER TRANSLATION
IPv6 host IPv6 header IPv6 header IPv4 host
Ipv4 header
payload payload payload
int. nodes int. nodes
int. nodes

12. SOME QUESTIONS
1.What is the main reason for switching fro IPv4 to IPv6 ?
Ans: IP address storage.
2. Identify any two differences b/w the IPv4 & IPv6 header format ?
Ans: 1. IPv6 use 360 bit while IPv4 uses 160 bits
2. IPv6 has 8 fields while IPv4 has 12 fields.
3. Explain the concept of tunneling ?
Ans: tunneling is a strategy used when two computers using IPv6
want to communicate, the packet must pass through some
region that uses IPv4. now to pass through this region, the IPv6
packet is encapsulated in an IPv4 packed and then it leaves its
capsule when it exit the region of IPv4.it seems that it goes
through a tunnel.
4. Name two main aspects in Internet security ?
Ans: 1. Authentication Header
2. Encapsulating Security Payload (ESP) Header