Understanding IP AddressBy: Noman Ahmed & Mujahid Hussain

What is IP• IP stands for Internet Protocol• a digital media transport system that runs over standard IP networks.• designed to allow one computer (or other digital device) to

communicate with another via the network. • IP address consists of four numbers, each of which contains one to

three digits, with a single dot (.) separating each number or set of digits.

• Example: 192.186.1.1 or 1.1.1.1 or 130.130.130.130

IP Address Classes

Class Range Network / HostsA 1 to 126 N . H . H. H B 128 to 191 N . N . H . H C 191 to 223 N . N . N . HD 224 to 239 Reserved for MultitaskingE 240 to 254 Experimental, reserved for

research

Note: Class A addresses 127.0.0.0 to 127.255.255.255 cannot be used and is reserved for loopback and diagnostic functions.

192.186.1.1 or 1.1.1.1 or 130.130.130.130

IP Addresses RangeClass Range Subnet Masking

A 1.0.0.1 to 126.255.255.254 Supports 16 million hosts on each of 126 networks.

B 128.1.0.1 to 191.255.255.254 Supports 65,000 hosts on each of 16,000 networks.

C 192.0.1.1 to 223.255.254.254 Supports 254 hosts on each of 2 million networks.

D 224.0.0.0 to 239.255.255.255 Reserved for Multitasking

E 240.0.0.0 to 254.255.255.254 Experimental, reserved for research

Note: Class A addresses 127.0.0.0 to 127.255.255.255 cannot be used and is reserved for loopback and diagnostic functions.

Subnet MaskingClass Range Example IP Subnet Masking

A 1 to 126 1 . 1 . 1 . 1 255 . 0 . 0 . 0

B 128 to 191 128 . 1 . 1 . 1 255 . 255 . 0 . 0

C 192 to 223 192 . 1 . 1 . 1 255 . 255 . 255 . 0

D 224 to 239 Reserved for MultitaskingE 240 to 254 Experimental, reserved for research

Note: Class A addresses 127.0.0.0 to 127.255.255.255 cannot be used and is reserved for loopback and diagnostic functions.

Subnet Mask

IP address breakdown• Every IP address is broken down into four sets of octets and translated

into binary to represent the actual IP address.

IP: 255 255 255 255

Binary value: 11111111 11111111 11111111 11111111

Octet value: 8 8 8 8

IP: 166 70 10 23

Binary value: 10100110 01000110 00001010 00010111

Numerical value: 128+32+4+2=166 64+4+2=70 8+2=10 16+4+2+1=23

NetID and HostID

Class-C: IP address breakdown

Network ID bits: 8 + 8 + 8 = 24

192.1.1.1 /24

Division Network Network Network Host

Subnet mask 255 255 255 0

Binary value: 11111111 11111111 11111111 0

Octet value: 8 8 8 0

Unicast addressing for smaller organizations with no more than about 250 hosts to connect to the Internet.

Unicast addressing for smaller organizations with no more than about 255 hosts to connect to the network.

Class-B: IP address breakdown

Network ID bits: 8 + 8 = 16

128.1.1.1 /16

Division Network Network Host Host

Subnet mask 255 255 0 0

Binary value: 11111111 11111111 0 0

Octet value: 8 8 0 0

Unicast addressing for smaller organizations with no more than about 250 hosts to connect to the Internet.

Unicast addressing for medium-to-large organizations with 65025 of hosts to connect to the network.

Class-A: IP address breakdown

Network ID bits: 8 = 8

1.1.1.1 /8

Subnet mask Network Host Host Host

Subnet mask 255 0 0 0

Binary value: 11111111 0 0 0

Octet value: 8 0 0 0

Unicast addressing for smaller organizations with no more than about 250 hosts to connect to the Internet.

Unicast addressing for very large organizations with 16581375 of hosts to connect to the Internet.

It’s all about Internet Protocol (IP)