What is Subnetting?
Subnetting refers to the modification of an IP (Internet Protocol) network into smaller ,more logical IP networks that are known as subnets. The technique is employed to divide the address space of a unicast address prefix for allocation among the subnets of an organizational network. The prefixes are said to be “efficient” because they waste fewer possible addresses that are then made available for assignments to the subnets of an organizational network. Subnetting is necessary when a network number requires to be distributed across multiple local area network (LAN) segments. There are several situations when this becomes necessary, including; * When an organization employs two different types of LAN technology, for instance, Ethernet and Token Ring * When two network segments are limited by distance and remote offices need connectivity * When segments need to be localized for network management purposes * When there is a need to isolate hosts with the greatest bandwidth requirements
A subnet is a segment of a network. Subnetting is a technique that allows a network administrator to divide one physical network into smaller logical networks and, thus, control the flow of traffic for security or efficiency reasons. Dividing a network into several subnets can serve a number of purposes: to reduce network traffic by decreasing the number of broadcasts (if used in combination with a switch), to exceed the limitations in a local area network, for instance the maximum number of allowed hosts, or to enable employees to be able to dial in to the network from home, without opening the entire network up to unwanted visits from the Internet. Subnets are created by using a so-called subnet mask to divide a single Class A, B, or C network number into smaller pieces, thus allowing an organisation to add subnets without having to obtain a new network number through an Internet service provider. Subnets can again be subnetted into sub-subnets. Subnets were originally invented to he
Subnetting is a network design strategy that segregates a larger network into smaller components. While connected through the larger network, each subnetwork or subnet functions with a unique IP address. All systems that are assigned to a particular subnet will share values that are common for both the subnet and for the network as a whole. A different approach to network construction can be thought of as subnetting in reverse. Known as CIDR, or Classless Inter-Domain Routing, this approach also creates a series of subnetworks. Rather than dividing an existing network into small components, CIDR takes smaller components and connects them into a larger network. This can often be the case when a business is acquired by a larger corporation. Instead of doing away with the network developed and used by the newly acquired business, the corporation chooses to continue operating that network as a subsidiary or an added component of the corporation’s network. In effect, the system of the purch
Subnetting is a method for maximizing the limited 32-bit IPv4 addressing space and reducing the size of the routing tables in a large internetwork. With any address class, subnetting provides a means of allocating a part of the host address space to network addresses, which lets you have more networks. The part of the host address space that is allocated to new network addresses is known as the subnet number. In addition to making more efficient use of the IPv4 address space, subnetting has several administrative benefits. Routing can become very complicated as the number of networks grows. A small organization, for example, might give each local network a class C number. As the organization grows, the administration of a number of different network numbers could become complicated. A better idea is to allocate a few class B network numbers to each major division in an organization. For example, you could allocate one Class B network to Engineering, one Class B to Operations, and so on
