Subnet Mask working

subnet mask working:

Communication between a node on a local subnetwork and a node on a different subnetwork is like communication between nodes on two different networks. To a user, routing between subnetworks is transparent. Internally, however, the IP software recognizes any IP addresses that are destined for a subnetwork and sends those packets to the gateway for that subnetwork.

When subnet masks are used, an IP address is interpreted as follows:

[IP address] = [Network address][Subnetwork address][Host address]

This shows that when a network is divided into subnetworks, the host address portion of the IP address is divided into two parts, the subnetwork address and the host address.

For example, if a network has the Class B IP network address portion 129.47, the remainder of the IP address can be divided into subnetwork addresses and host addresses. This division is controlled by the network administrator to allow the most flexibility for network development at the site.

A subnet mask is the mechanism that defines how the host portion of the IP address is divided into subnetwork addresses and local host address portions. The subnet mask is a 32-bit, (four byte) number, just as an IP address is.

To understand the mechanics of the subnet mask, it is important to know a little of binary arithmetic.

CLASSLESS INTER DOMAIN ROUTING(CIDR)

CIDR is the method that ISP (Internet Service Provider) use to allot the IP Address to companies or Home or College or Customer .They provide in a certain block size

when you recieve address from Internet service Provider that will get like this 192.168.10.32/28

  

For Example This will be telling  you what the subnet mask is?

We will Discuss in Next Post this is the must Important Chapter for understanding  IP Address ?