Standard portlets publish and subscribe mechanisms

Both JSR 168 and 286 portlets provide communication capabilities that enable you to pass information from one portlet to another. For JSR 286 portlets, these capabilities are included in the JSR 286 standard. For JSR 168 portlets, an extension defined by HCL provides these capabilities. Portlet developers define these capabilities. Portal administrators then determine whether or not these capabilities are used to pass information between portlets.