The Sesame architecture is based on :
Filters (from Servlet API 2.3) : The Filters are
pluggable components that are used to process HTTP requests and
generate HTTP response. They are the processing elements of Sesame.
New filters can be developped and plugged seamlessly into Sesame or
existing ones can be replaced.
Services (using the Avalon architecture): They
provide services for the Filters such as a logging service, an XML to
Java mapping service, etc.