What is the significance of subnet mask

This method divides a network into smaller subnets. It also helps you to reduce the size of the routing tables, which is stored in routers. A subnet mask is a 32 bits address used to distinguish between a network address and a host address in IP address. A subnet mask identifies which part of an IP address is the network address and the host address.

They are not shown inside the data packets traversing the Internet. They carry the destination IP address, which a router will match with a subnet. The subnet mask is used by the router to cover up the network address.

It shows which bits are used to identify the subnet. Every network has its own unique address, Like here, class B network has network address Example IP address: All traffic destined for that remote host should be directed to the router indicated in the source host's routing table. If no explicit route is defined in the routing table, the traffic is directed to the source host's default gateway.

Figure 3. Host A with IP address If the subnet mask for Host A is When converted to binary, the address As you can see, the two results match. This indicates that, as far as Host A is concerned, the two hosts are on the same physical network. Communication can occur directly between the two hosts. In fact, the same holds true because host B would have the same subnet mask since the hosts are on the same network. Day 5, "The Art of Subnet Masking," further examines the art of subnet masking.

It also examines the use of nonstandard subnet masking to further segment a group of IP addresses into smaller segments. As previously discussed, the subnet mask determines whether a destination host is on the local network or a remote network. You can communicate with hosts on the local network, but you can't communicate with remote hosts.

You can communicate with all hosts on the remote network except one specific host. When you try to communicate with that host, you receive messages such as Timed out warnings.

You can't communicate with a host on the local network because your host believes it is located on a remote network and incorrectly forwards the packet to the default gateway. I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Pearson Education, Inc. This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site.

Please note that other Pearson websites and online products and services have their own separate privacy policies. To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:. For inquiries and questions, we collect the inquiry or question, together with name, contact details email address, phone number and mailing address and any other additional information voluntarily submitted to us through a Contact Us form or an email.

We use this information to address the inquiry and respond to the question. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes. Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites.

Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey. Occasionally, we may sponsor a contest or drawing. Participation is optional.

Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information informit.

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email.

Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent.

You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience. Necessary Necessary. Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously. The cookie is used to store the user consent for the cookies in the category "Analytics".

The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is used to store the user consent for the cookies in the category "Other. The cookie is used to store the user consent for the cookies in the category "Performance". It does not store any personal data. Functional Functional. Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.

Performance Performance. Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. Analytics Analytics.

Analytical cookies are used to understand how visitors interact with the website.