2. Chapter Objectives
Explain TCP/IP protocol stack
Explain IP addressing
Discuss IP subnetting
Plan IP addressing
Chapter 2 2
3. Recall
Physical and the Logical topology are the two types
of topologies
LAN, MAN and WAN are the different types of
networks used
Hierarchical model includes three layers, core layer,
distribution layer and the access layer
Application layer, presentation layer, session layer,
transport layer, network layer, data link layer and the
physical layer are the different layers of the OSI
model
Chapter 2 3
4. TCP/IP Stack
TCP/IP stack has four layers
TCP/IP
Network
Application
Interface
Transport Internet
Chapter 2 4
5. Application Layer
Application layer clubs the functionality of application,
presentation, and session layers of the OSI model
Protocols that function at the application layer include
Hyper Text Transfer Protocol (HTTP)
Simple Network Management Protocol (SNMP)
File Transfer Protocol (FTP)
Telnet
Chapter 2 5
6. Transport Layer
Layer is responsible for source-to-destination
delivery of the entire message
Ensures that the entire message arrives at the
destination computer
Protocols that function in the transport layer include
TCP
User Datagram Protocol (UDP)
Chapter 2 6
7. Internet Layer
Layer allows routing of data over the network
Protocols that function in the network layer include
Address Resolution protocol (ARP) - ARP
provides a method for finding the Media Access
Control (MAC) address of the host computer from
its IP address
Reverse Address Resolution Protocol (RARP) -
RARP provides a method for finding the IP
address of the host computer from the MAC
address
Chapter 2 7
8. Internet Control Message Protocol
(ICMP)
ICMP functions at the network layer of Internet
Protocol
The protocol reports errors related to the delivery of
IP packets within a network
ICMPs generate the following four messages
Destination Unreachable message
Echo request message
Redirect message
Time exceeded message
Chapter 2 8
9. IP Addressing
IP address is a 32-bit binary number that is unique for each
device
IP address is converted to a decimal format to make them
readable for the humans
Within the network, the IP address is interpreted in a binary
format consisting of 0 and 1
IP address of 10010100101000101001010010101011, it is
split into 4 octets such as
10010100
10100010
10010100
10101011
Chapter 2 9
10. IP Addressing
To convert the bits to a decimal format, right most
bit in the octet has the least value of 20. This value
goes on increasing towards the left
Bits 1 0 0 1 0 1 0 0
Values 27 = 128 26 = 64 25 = 32 24 = 16 23 = 8 22 = 4 21 = 2 20 = 1
Chapter 2 10
11. IP Addressing
You need to multiply the bits with its corresponding
value in the table
Bits 1 0 0 1 0 1 0 0
Values 27 = 128 26 = 64 25 = 32 24 = 16 23 = 8 22 = 4 21 = 2 20 = 1
Multiplied 128 0 0 16 0 4 0 0
Values
Chapter 2 11
12. IP Addressing
The equivalent decimal value for the octet will be the
addition of all the multiplied values
For the octet 10010100, the decimal value will be
128+0+0+16+0+4+0+0 = 148
So the IP address of the machine will be
148.162.148.171
Chapter 2 12
13. Classification of IP Addresses
CLASSES
Class A Class B Class C Class D Class E
1-126 128 - 191 192 -223 224-239 240 - 255
Chapter 2 13
14. IP Address Components
A network number denotes the network segment to
which the device is connected
A host number specifies the address of the device in
the network segment. Host numbers are the
numbers between the network number and the
directed broadcast number
Chapter 2 14
15. Subnet Mask
Subnet mask is used to identify the network bits and
host bits in the IP address
A subnet mask always has a series of consecutive
1s followed by consecutive 0s
A subnet mask cannot start with the bit 0 or ending
with the bit 1
Chapter 2 15
17. Algorithm to determine the number of
hosts and subnets
Identify the IP address structure
Determine the number of network bits based on the
class of the IP address
Determine the number of host bits based on the
number of 0s in the mask
Determine the number of host bits using the formula,
32 – (network bits + host bits)
Calculate the number of subnets using the formula,
2subnet bits – 2
Calculate the number of hosts in each subnet using
the formula, 2host bits – 2
Chapter 2 17
18. Case Study
The Blue Diamond Steel organization located in
Gujarat is granted an IP address 220.56.64.0 by
Internet Assigned Numbers Authority (IANA). The
company requires five different subnets for its
Finance, Business Development, Software
Management, Project Management and Detailing
departments. The network administrator Robert needs
to design the subnets for the company.
Chapter 2 18
19. Problem
Finding IP address range for each subnet
Chapter 2 19
21. Variable Length Subnet Mask (VLSM)
VLSM allows you to use different masks for each
subnet
Classful protocols such as Routing Information
Protocol version 1 (RIPv1) and IGRP do not support
VLSM
Advantages of VLSM include
Efficient use of IP addressing
Route summarization
Chapter 2 21
22. Route Summarization
Advantages of route summarization include:
Reduction in the size of routing table, memory
requirement and time for processing
Reduction in the size of updates and bandwidth
requirement
Detection of networking problems that ensures
proper routing of the packets to the destination
Chapter 2 22
23. VLSM Design
A VLSM design ensures efficient use of available IP
addresses as well as more-efficient routing update
communication using hierarchical IP addressing
Design criteria that affect the functioning of the
VLSM technology include
Total subnets required currently
Total subnets that may be required in the future
Number hosts on the largest subnet currently
Number of hosts that may be required on the
largest subnet in future
Chapter 2 23
24. Planning IP Addressing
Planning IP addressing include
Identifying Network and Host Requirements
Calculating Subnet Masks
Identifying Network Addresses
Identifying Directed Broadcast Addresses
Identifying Host Addresses
Chapter 2 24
25. Summary - I
TCP/IP is a protocol suite that allows data transfer
between network devices
The Application layer clubs the functionality of
application, presentation, and session layers of the OSI
model
The transport layer is responsible for source-to-
destination delivery of the entire message
The network layer allows routing of data over the
network
The data-link layer allows the source computer to add
meaningful bits to the data packet so that the destination
computer identifies it
Chapter 2 25
26. Summary - II
Every device that is connected to the network using the
TCP/IP protocol requires an IP Address
The IP address is a 32-bit number that is unique for each
device
The IP address is converted to a decimal format to make
them readable for the human eye
The 32-bit binary IP address is represented as 4 octets,
each consisting of 8 bits
Every IP address consists of two parts, the network, and
the host number
The network number identifies the network segment and
the host number identifies the actual device
Chapter 2 26
27. Summary - III
Host numbers are the numbers between the
network number and the directed broadcast number
Subnetting refers to the process of grouping a
definite number of devices
A subnet mask allows us to identify the network
number and the host number of an IP address
A subnet mask contains 32 bits similar to IP
addresses and is represented in a decimal form
separated by periods
Chapter 2 27
28. Summary - IV
In a binary format, the bit 1 in the subnet mask
represents the network number and the bit 0
represents the host number
A subnet mask always has a series of consecutive 1s
followed by consecutive 0s
The higher order bits are always reserved for
subnetting
The boolean AND operation enables us to identify the
subnet number in an IP address
The directed broadcast address specifies all host
addresses on the particular network
Chapter 2 28
29. Summary - V
You can calculate network and host requirements
using the following formulae:
2X = > number of networks, where X refers to
number of subnet bits
2Y – 2 = > hosts on largest segment, where Y
represents the host bits.
X + Y <= total host bits
Variable Length Subnet Mask (VLSM) allows you to
use different masks for each subnet to prevent the
wastage of address space
Chapter 2 29
