BOB SHARE

IPv4 and Addressing

Introduction


Your introduction here

Objectives


Learn about IP address
Learn about IP allocation
Concept of public and private IP
Concept of loopback IP
Concept of Network and Broadcast ID

Learn about IP address


IP (Internet protocol) is numeric identification of  device in computer network.
Every device in computer network has a unique IP address.
IP is 32 bit long.
Binary but represented as decimal
Separated by . in four octets.
Example of IP address
00000100.00000010.00000010.00000010
is an example of IP address in binary form.
Notice . in every octet
4.2.2.2 is the same IP address in human readable decimal form. (dot-decimal notation)
116.197.164.1, 202.63.242.6, 10.10.5.211 are other examples.
74.125.45.100 is one of the IP of google.com

IP allocation


Originally, an IP address was divided into two parts:
Host and Network
Only 256 Network possible with this allocation
To overcome this problem IP allocated as classful Network
Allocated as CIDR
Classful Network
IP address divided into five class.
Class A,B,C,D and E
Each class defines size of the network and type(unicast or multicast).
In each network there is 2N-2 host address available where N is number of bits for host part.
IP with all bits 0 and all bits 1 cant be used for hosts.
Replace by CIDR from 1993.

CIDR


Classless Inter-Domain Routing
Main problem of classful network - too small for most enterprises, and the next larger block contained 65,536 addresses—too large to be used efficiently by even large organizations
Uses CIDR notation to specify IP address.
134.13.1.0/21 example of CIDR notation

Public and Private IP


Private IP addresses are unroutable address
Private IP address are not globally assigned
Private IP addresses created due to shortage of public IP
One IP range in class A,B and C separated as private IP
Private IP cant be used in Internet
Private IP
Localhost
address range 127.0.0.0–127.255.255.255
Packets sent to this address returns to the same interface
Called as loopback

Network and Broadcast ID


IP address with all bits zero in the host part is the network ID.
For example 192.168.0.0 is network ID for /24 network.
IP address with all bits one in the host part is the broadcast ID for the network.
For example 192.168.0.255 is broadcast ID for /24 network.
Broadcast ID used for sending packets to all device under the network.

Conclusion


We are running out of address in IPv4
IPnG or Ipv6 is currently being implemented to solve this issue.
IPv4 is 32 bit whilst IPv6 is 128 bit.
IPv6 is supported on Linux, Mac OS and Windows.
IP allocated as CIDR.
Private IP cant be used in Internet.

Question

Download the ppt slides for IPv4 And Addressing presentation from here.