Application performance issues can affect the bottom line, especially in a mission-critical situation. Developers diligently strive to produce elegant and efficient software. Prior to releasing an application, developers run functional and regression tests, along with stressing the server to ensure an optimized application.

Developers typically test applications in a perfect environment, with high bandwidth and low latency. However, once the application moves from the local (or test) environment to the production network, clients may complain about the slow response times. The programmers carefully check the application, however, are unable to find anything unusual.

The developer must determine the reasons for the slow response times. Once further testing determines that it is not the application that is causing the issue, a packet analysis tool such as Wireshark can assist the developer in determining the root cause of the delayed response times.

By using Wireshark, the developer can uncover common problems in transmissions, such as round-trip time and signs of congestion within an organization, which can occur in a network and impact response time.

Developers will understand that simply optimizing an application is not enough, and all development life cycles should include seeing what is happening on the network, as issues can affect overall performance.

In addition to developers, network administrators commonly use Wireshark to troubleshoot the network, as we will see next.