Internet Protocol Design and Subnetting

People sometimes talk about IP address and many sort of things about networking, TCP/IP etc. But how many of us do actually knows what IP stands for? What it is used for? What actually is IP? Here are the fundamental of Internet Protocol.

What is Internet protocol?

• Sets of rules to communicate
• Used for communication in a network

What is IP address?

• Unique addressing for each device on a network
• Usually a numerical label
• Divided into 2 version, IP version 4 (IPv4) and IP version 6 (IPv6)

IPv4

• IPv4 uses 32 bits (4-bytes) address
• Address space limits to (2^32) 4,294,967,296
• IPv4 addresses is predicted to run out in the next two years, so an alternative is required
• For example, An IP address that computers see as :

         00001010 00000000 00000000 00000001 in dotted decimal as : 10.0.0.1

IPv6

• IPv6 uses 128 bits (16-bytes) address
• This larger size means that IPv6 supports more than :     

         300,000,000,000,000,000,000,000,000,000,000, 000,000

• In the coming years, as an increasing number of cellphones,PDA's,other expand their network capabilities, the smaller IPv4 and IPv6 addresses become necessary
• IPv6 address are generally written in the following form :

         hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh

• Pairs of IPv6 bytes are separated by a colon & each bytes in turn is represented as a pair of hexadecimal numbers, example :

         E3D7::0000:0000:0000:51F4:9BC8:192.168.100.32

• Many IPv6 addresses are extensions of IPv4
• In these case, the rightmost four bytes of an IPv6 address (the rightmost two byte pairs)

        maybe rewritten in IPv4 notation

• Converting the above example to mixed notation yields :

         E3D7::51F4:9BC8:192.168.100.32

        *IPv6 address maybe written in any of the full, shorthand or mixed notation

         illustrated above

IP Address Class

Subnetting

What is IP Subnetting?

• A subnet allows flow of network traffic between hosts to be segregated based on a

         network configuration

• Subnetting is used to break the network into smaller, more efficient subnets to prevent

         excessive rates of Ethernet packet collision in a large network.

• By organising hosts into logical groups, subnetting can improve network security and performance

Why used Subnetting?

*Before Subnetting

• Broadcasting high
• Data collision high
• Network performance low

*After Subnetting

• Broadcasting low
• Data collision low
• Network performance high

Subnet mask

• A significant feature of subnetting is the subnet mask
• Similar to IP Address, a subnet mask contains four bytes (32 bits) and is often written

         using the same "dotted-decimal" notation

• A subnet mask separates the IP Address into the network and host address (<network><host>)

Uses of subnet mask

• Identifies a network
• Isolate the network ID and Host ID
• Determines the number of host/terminals that could be use on the same network
• Reduces network traffic