Final answer:
Step three of isolating a network problem is to identify exactly what needs to be determined, or the unknowns, by making a list of potential causes and testing the obvious solutions. This helps in systematically troubleshooting the issue.
Step-by-step explanation:
The third step in the process of isolating a network problem involves identifying exactly what needs to be determined in the problem, which is identifying the unknowns. In complex network issues, it's crucial to understand that it may not be immediately clear what the root cause of the problem is. Therefore, making a list of possible causes and testing the obvious solutions can be extremely helpful. This step comes after gathering information about the network's configuration, the symptoms being experienced, and any recent changes to the system that might have triggered the issue.
Once the unknowns have been identified and a list of potential causes has been made, you can begin to systematically test each one to see if it solves the problem, ensuring a structured approach to troubleshooting the network issue.