# A GeoNode-Based Platform for an Effective Exploitation of Advanced DInSAR Measurements
## 1 Introduction
We underline that the interoperability concept can be defined, following the definition provided by the International Interoperability Working Group [40], as a characteristic of a product or system, whose interfaces are completely understood, to work with other products or systems, present or future, in either implementation or access, without any restrictions; more practically interoperability, in the context of the OpenGIS Specification, is software components operating reciprocally (working with each other) to overcome tedious batch conversion tasks, import/export obstacles, and distributed resource access barriers imposed by heterogeneous processing environments and heterogeneous data [41]. This is extremely important because interoperability allows the data producers to share geospatial information for all types of cooperative processes, thus avoiding duplication of efforts and costs. In the past, governmental SDIs were mainly centralized structures whereas nowadays they are designed as interconnected local entities, with great interoperability and better cost optimization [38]. In this way, different types of data can be managed with a distribution of work and responsibility that simplifies the data sharing process between different organizations both public and private. Moreover, the interoperability allowed by the use of open standards has changed and made simpler the way of working and the coordination among institutions. Indeed, today OGC standards are widely implemented in many software platforms, both open source and proprietary ones, allowing data integration among different products. Indeed, it is now possible to access data and services from hundreds of sources through the use of Web interfaces, and the SDI administrators now may choose among several options. A Desktop Geographic Information System (GIS), which is a framework that acquires, analyzes, manages, stores, extracts, transforms and visualizes geographical and spatial data [39; 42], can still have its original purpose, but now it can also be put online so that users can remotely access the data, becoming a web accessible resource. These sources can be recorded with metadata in catalogs available on the web so that they can be found and retrieved easily, making the integration easier than ever. Moreover, client applications and in some cases the server processes,can now run on mobile devices as easily as on desktops, making possible the development and exploitation of new applications [38]. On the other hand, we remark that the actual SDI users require the implementation of new functions that go beyond the traditional visualization and data management options. Indeed, researchers that traditionally were using GIS, now require data infrastructures that can integrate different types of data, in which there is not only the spatial but also the temporal component, that can be extremely relevant when analyzing surface deformation phenomena. Accordingly we present in this work an efficient displacement measurements tool to perform analysis on both the spatial and temporal characteristics of the DInSAR displacements that, in this study, have been obtained through the advanced DInSAR approach referred to as Small BASeline Subset (SBAS) technique [29] and are relevant to acquisition in Italy of the Sentinel-1 SAR sensors constellation. In particular, we focus on the GeoNode platform [43] which was originally designed for building GIS and SDI, based on the OGC standards. The key idea of the paper is to extend the GeoNode functionalities in order to obtain an SDI allowing us to effectively manage, visualize, analyze, and integrate it with other data sources, large data volumes of DInSAR time-series and their related products. Moreover, the implemented modifications on the GeoNode platform permit the user to straightforwardly integrate the exploited DInSAR measurements with those obtained from other sources, such as, for example, digital cartography, maps extracted from data sensed from different satellite platforms, GPS measurements.