There could be hundreds of thousands of devices that are connected within a network, and the corresponding IP addresses can create a complex route that traffic must travel. Subnetting limits the IP address usage to within a few devices. This allows an engineer to use subnetting to create sub-networks, sorting data so that it can travel without touching every part of the more complex routers. To do this, an engineer needs to match each IP address class to a subnet mask.
A subnet mask echoes an IP address, but it can only be utilized within an internal network. This mask helps to identify which part of the IP address relates to the network and which part relates to the host so specific data is sent on particular routes according to its destination. A subnet mask creates the tool that enables a router to match an IP address with a sub-network.
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