What is the purpose of a subnet mask?

The purpose of a subnet mask is to divide an IP address into two main parts: the network portion and the host portion. This division is essential for routing packets of data within networks. The network portion identifies the specific network to which the device belongs, while the host portion specifies the particular device (host) on that network.

This process allows multiple devices to communicate efficiently within the same network and enables proper routing of information across different networks. By using a subnet mask, network administrators can design and manage networks more effectively, allowing for better utilization of IP address space and improved overall network management.

In contrast, functions such as converting domain names into IP addresses or protecting devices from malware relate to different aspects of networking and security, while increasing the speed of internet connections involves factors such as bandwidth and protocol optimizations, not the role of a subnet mask.