This document discusses internet layer protocols and IP addressing. It covers the OSI reference model and protocols of the internet layer like IP, ICMP, ARP, and RARP. It also explains IP address classes A, B and C and the ranges they cover. Finally, it discusses private IP addresses and their use on private networks.

1. 1
Shudhanshu Agarwal
B.tech (EC-2011)
Roll no.-1101421102

2. 1. Introduction
2. Internetworking Models
3. Internet layer protocols
4. IP Addressing
5. Private IP addresses
6. Conclusion
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3.  Two main reasons for using Internet
Layer :
1. For routing
2. Providing a single network interface
to upper layer s
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4.  Protocols of Internet layer
1. Internet Protocol
2. Internet Control Message Protocol
3. Address Resolution Protocol
4. Reverse Address Resolution Protocol
5. Proxy ARP
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5. In 1970s OSI Reference Model was
formed.
Helped the different vendor networks to
communicate.
Describes data and information transfer
from one to another computer.
The OSI has seven layers ,divided into
two groups :
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6. 1. The upper layers :
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7. 2. The lower layers :
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8. Looks at each packets address.
Helps in identifying the devices.
Receives segments from host-to-host
layer and fragments them into
datagrams .
The IP Header gives the idea of what
the IP protocol has to go through.
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10. It is a management protocol and
message service provider for IP.
Its packets :
1. Can provide host with information
about network problems.
2. Are encapsulated within IP
datagrams.
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12. Finds the hardware address of a host
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13. Requests for an IP address for a
particular MAC address :
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14. Help machines on a subnet reach
remote subnets without configuring
routing or even a default gateway.
It can be added to a single router
without disturbing the routing tables
of the other routers.
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15. It is a software address.
It was designed to allow hosts on one
network to communicate with the host on
different network.
It consists of 32 bits of information and
these bits are divided into four equal
octets separated by a dot.
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16.  Bit
 Byte
 Octet
 Network Address
 Broadcast Address
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17. Network address : It uniquely
identifies each network.
Node address : It uniquely identifies
each machine on a network.
The designers of Internet created
classes of network based on the
network size.
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18. The various classes of networks are :
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19. Here the first bit of the first byte must
be off, or 0.
Address must be between 0 and 127.
Consider the following network
address:
0 x x x x x x x
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20. If we turn the other 7 bits all off and
then turn them all on ,we’ll find the
range of class A network address:
00000000 = 0
01111111 = 127
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21. Here the first bit of the first byte
must always be turned on but the
second bit must always be turned off.
Address must be between 128 and
191.
Consider the following network
address:
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22. 1 0 x x x x x x
If we turn the other six bits all off and
then turn them all on ,we’ll find the
range of class B network address:
10000000 = 128
10111111 = 191
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23. Here the first two bits of the first
octet are always turned on but the
third bit can never be on.
Address must be between 192 and
223.
Consider the following network
address:
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24. 1 1 0 x x x x x
If we turn on other five bits all off and
then turn them all on, we’ll find the
range of class C network address.
11000000 = 192
11011111 = 223
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25. The addresses between 224 and 255
are reserved for class D and E
networks.
Class D(224-239) is used for multicast
addresses .
Class E (240-225) is use for scientific
purposes.
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28. First byte : network address.
Remaining bytes : node address.
Format is:
network.node.node.node
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29. First two bytes : network address.
Remaining two bytes : node address.
Format is
network.network.node.node
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30. first 3 bytes : network address.
Last byte : node address.
Format is:
network.network.network.node
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31. It is used on private network.
It saves IP.
It uses Network Address Translation
to accomplish the task.
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33. Overview of OSI reference model
About IP ,ICMP, ARP, RARP,
Proxy ARP
use of Class A ,B and C Addressing
Importance of Private IP Address.
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