| 9.2 |  | Network Testing |
| 9.2.1 |  | Introduction to network testing |

| Basic testing of a network should proceed in sequence from one OSI reference model layer to the next. It is best to begin with Layer 1 and work to Layer 7 if necessary. Beginning with Layer 1, look for simple problems such as power cords plugged in the wall. The most common problems that occur on IP networks result from errors in the addressing scheme. It is important to test the address configuration before continuing with further configuration steps. Each test presented in this section focuses on network operations at a specific layer of the OSI model. The commands telnet and ping are two important commands that are used for testing a network.
| Interactive Media Activity Point and Click: Network Testing After completing this activity, the student will be able to understand network testing.
| Web Links Tools, Maintenance, and Troubleshooting Tips for Cisco IOS Software http://www.cisco.com/en/US/products/ sw/iosswrel/ps1828/prod_ troubleshooting_ technique09186a008010929b.html