Title: AEGIS – A state-of-the-art component based spatio-temporal framework Length: 4 106 words, 16 pages Stated objective of the article The authors’ objective is to present the AEGIS framework, a spatio-temporal data management system currently under development at the authors’ institute, and to demonstrate its use through case studies. Title The title reflects the content of the paper, but I suggest that you include the purpose of the framework in the title. Abstract The abstract reflects the content of the paper. Review The article presents the AEGIS platform or framework. Its system architecture, spatio-temporal data model and data processing capabilities are described, as well as the preliminary results of two applications in which the framework was used. It is an interesting (but not novel) concept to develop a framework for use in research and education. The authors provide a general overview of AEGIS and it is not clear what the scientific contribution of the paper is. This is a pity, because there should be many possible contributions from work on a framework such as the one described. The general overview of the framework makes this paper more suitable for the general than the academic track. A further concern is that a Google search for ‘spatio-temporal index aegis’ detected a similar paper with the title ‘Towards the new open source GIS platform AEGIS’ at http://people.inf.elte.hu/groberto/kutatas/publikaciok/ GIZ2012_abstract_giachetta_laszlo_balint.pdf. Even though the content of the two papers differ, the abstracts and conclusions are almost identical. The reviewed paper lists four anonymous papers by the authors, so one cannot confirm whether one of these is to the paper at the URL above. The authors need to confirm that the paper at the URL above is indeed referenced in the FOSS4G2013 submission. In addition, the authors need to clarify the difference between the paper at the URL above and the paper submitted to FOSS4G2013. Below a few detailed comments on individual sections of the paper: 2. System architecture According to the authors the IO component supports standard spatial formats and services such as WMS and WFS. However, on the next page, they explain that the Services component provides web services such as WMS. Do they both provide services such as WMS? That does not make sense… 5. Applications In the abstract the authors refer to ‘case studies’, whereas here they refer to ‘applications’. Consistent terminology should be used. References The ISO standard cited in the text is not correctly referenced listed in the references. It should be: ISO 19108:2002, Geographic Information – Temporal schema. International Organization for Standardization, Geneva, Switzerland. OpenGIS specifications are published by the Open Geospatial Consortium (OGC), therefore their name should be included as publisher in references to OpenGIS specification. Furthermore, each OpenGIS specification has a different version number, which should also be included in the reference. The OpenGIS documents (with version number details) are freely available at www.opengeospatial.org. Language The article is well-written and easy to follow. There are minor typo and grammar issues, for example: p3: Remove ‘a’: ‘Processing offers a spatio-temporal vector/raster processing operations.’ → ‘Processing offers spatio-temporal vector/raster processing operations.’ p4: Insert ‘a’: ‘Communication uses service oriented architecture …’ → ‘Communication uses a service oriented architecture …’ p5: Add ‘s’ to ‘application’: ‘The usage of Core components is recommended in application where no temporal features are needed.’ should be ‘The usage of Core components is recommended in applications where no temporal features are needed.’ p6: ‘…on a sinlge pixel…’ → ‘…on a single pixel…’ p14: Replace ‘s’ with ‘w’: ‘…customization possibilities shich are needed for…’ → ‘…customization possibilities which are needed for…’