WebSpeed
Developer’s Guide


How WebSpeed Handles a Request

This section describes how the components of the WebSpeed Transaction Server interact to respond to a request from a client browser. The basic request cycle is the same for the WebSpeed Development Server, Transaction Server, or the Enterprise Transaction Server. The basic request cycle is also the same for all types of Web objects.

  1. The Web server receives the request from an Internet browser. Each request is in the form of a URL:
  2. The Web server spawns a CGI Messenger or wakes up a previously spawned ISAPI or NSAPI Messenger:
  3. The WebSpeed Messenger sends a request to the NameServer for an available WebSpeed Broker:
  4. The Messenger initiates a connection to the WebSpeed Broker at the address returned by the NameServer and forwards the request to that Broker:
  5. NOTE: Under the WebSpeed Enterprise Transaction Server, the NameServer can manage multiple WebSpeed Brokers that support the same application service. It will choose a broker based on load-balancing criteria.

  6. The WebSpeed Broker consults its pool of WebSpeed Agents and assigns the request to an idle Agent:
  7. The WebSpeed Agent and the WebSpeed Messenger establish a connection. The Web object name and the environment for the request are passed to the Agent:
  8. The WebSpeed Agent executes the Web object. It also performs the necessary reads from and writes to the database. Notice that the WebSpeed Agent maintains its connection with the WebSpeed Messenger while the Web object is executing:
  9. The WebSpeed Agent passes the generated HTML Web Page to the Messenger, which sends it to the browser through the Web Server:
  10. A state-aware Web object, although no longer executing, maintains a persistent context for later execution by the Agent. For more information about stateless and state-aware Web objects, see Controlling WebSpeed Transactions."

    After completion, the Agent disconnects from the Messenger, and the Agent updates its availability with the Broker. The Web server disconnects from the browser after sending the HTML Web Page.


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