In this chapter, we'll cover session management in JMeter in detail. Web applications, by their very nature, use client and server sessions; both work in harmony to give each user a distinct enclosure to maintain a series of communications with the server without affecting other users. For example, in Chapter 2, Recording Your First Test, the server session was created the moment a user logged in to the application, and was maintained for all requests sent to the server by that user until he/she logged off or timed out. This is what protects other users from seeing each other's information. Depending on the application's architecture, the session may be maintained through cookies (most commonly used) or URL rewriting (less commonly used). The former maintains the session by sending a cookie in the HTTP headers of each request, while the latter rewrites the URLs to append the session ID. The main difference is that the former relies on a client's browser choosing...