What is an agreed-upon set of rules that data use to move through a network?

• A. Network protocol
• B. IP address
• C. Subnet mask
• D. DNS

Answer: (A)

The main idea here is network protocol. A protocol is an agreed-upon set of rules that govern how data moves through a network. It covers how data is formatted into packets, how devices establish and terminate communication, how errors are detected and corrected, how packets are sequenced, and how access to the communication medium is managed. This shared rule set lets different devices and networks interoperate, so data can travel reliably from one end to the other. For example, web traffic typically uses the HTTP protocol layered on top of TCP, which in turn runs on the IP protocol—the whole protocol suite guiding how messages are sent, received, and interpreted.

An IP address identifies a specific device on a network, like a unique mailing address for a host. A subnet mask helps define which portion of an IP address refers to the network versus the host, aiding routing within a local network. DNS is a naming service that translates human-friendly domain names into IP addresses. None of these alone define the rules for how data moves; that role belongs to the network protocol.