Esri Geoportal Server is a open source product released under Apache 2.0 license. It helps organizations meeting INSPIRE compliance via a INSPIRE metadata editor and INSPIRE Discovery Service implementation based on version 3.0 of the technical guidance. For further details you can visit http://geoportal.sourceforge.net/ This is Saher from IMMAP. Our Organization is planning to design a NSDI, therefore I am caring out a comparative study between Geonetwork, ESRI GIS Portal Toolkit 9.3.1, ESRI Geoportal Extension 10 and ESRI Geoportal Server (Open Source). I have studied the user and developer manuals but still there are few things which are not clear at technical and architectural level. Please help me with the following questions. Your help will help us to reach to some conclusion that whether to use Geonetwork, ESRI Geoportal ToolKit / Extension or ESRI Geoportal Server :- 1. What is the security at application level (e.g. Particular data access to an individual in a group, etc.) and system level (e.g. Can individual Nodes have full access to all hierarchies within the portal) in ESRI GIS Toolkit/ ESRI Geoprtal Extension and ESRI Geoportal Server (which is an open source)? 2. Is the security level the same in ESRI Geoportal Server for both it’s commercial and open source products? 3. What are the functionalities in ESRI GIS Toolkit & Extension (i.e. Commercial) that is not present in ESRI Geospatial Server (i.e. Open source) and vice versa? 4. If we want to use ArcGIS Server with Geonetwork then do we need to purchase the ESRI license for it or ArcGIS Server Online is enough for it? 5. Other then the cost why organizations prefer open source like Geonetwork / ESRI Geospatial Server? 6. What is special about ESRI Geoportal Server (i.e. Open Source) that the organization must go for it rather than ESRI GIS Toolkit / Extension (i.e. Commercial)? 7. Can we also connect with other ESRI products via Geonetwork. For example: a. Direct modification of vector or raster layer from ArcMap or any other such tool/technology b. Directly updating Metadata from ArcCatolog or any such other tool/technology. c. Or any other map viewer like ArcExplorer, ArcGlobe, ArcScene, etc.? 8. Can we also connect with other ESRI products via ESRI Geospatial Server which is an open source. For example: a. Direct modification of vector or raster layer from ArcMap or any other such tool/technology b. Directly updating Metadata from ArcCatolog or any such other tool/technology. c. Or any other map viewer like ArcExplor1er, ArcGlobe, ArcScene, etc. 9. If both ESRI Geoportal commercial and open source Servers provide the same functionalities and secutity then why companies opt for commercial which is very costly and management is also difficult Source.