Geoportal website access: The USC Geoportal website (http://geospatial.usc.edu/geoportal) is directly accessible from the USC network on campus. Anyone on campus using a mobile device such as a laptop, tablet PC or a smart phone needs to establish a secure VPN connection to the USC network prior to accessing the Geoportal website. Instructions for connecting via VPN can be viewed here.
Anyone outside of the USC campus can access the USC Geoportal website using https://libproxy.usc.edu/login?url=http://geospatial.usc.edu/geoportal/catalog/main/home.page From this link you will be asked to login using your USC credentials and you will then be redirected to the USC Geoportal website.
Compatibility with ArcGIS 10.1: The map services and spatial data available on the Geoportal are pre-processed through ArcGIS version 10.1. So any user wishing to utilize map services in ArcMap will need ArcGIS version 10.1. It is also important to note that any user wishing to download data in geodatabase format needs to have ArcGIS 10.1 version to display data in ArcMap or ArcCatalog. An alternative to downloading the data via a geodatabase, is to download data in the shapefile format. A shapefile format will allow a user to open the data in any version of ArcGIS or other GIS software platforms that can view shapefiles. Similarly, a user can choose to view map services in the integrated Map Viewer (accessible via Launch Map Viewer menu item), or in ArcGIS Explorer software (free) or in the Google Earth software (free) if ArcGIS 10.1 software is not available.
Demonstration videos: We have created short screen cast videos to utilize data and services available on the SSI Geoportal. These videos can be viewed on the Demos page of the Geoportal website. Please view these to become familiar with browsing, viewing, and downloading data from the Geoportal website. Each video is of 5-10 minute duration.
Data download: There are currently over 60 layers available for download on the SSI Geoportal. A detailed list of data layers can also be viewed here. If using a keyword search for data, please note that search keywords accept a wildcard *. When a data download request is submitted on the Geoportal website, the web server sends this request to an ArcGIS Server, and the ArcGIS server runs a geoprocessing web service that actually clips the data to the extent specified by a user. Currently there is one ArcGIS server to handle to the data download requests. The server allocates each task a maximum of 20 minutes of processing time, and if the task exceeds this time limit then the server sends a message on the data download page informing the user that the download task failed due to a time-out limit. In such a case, the user can reduce the number of layers requested for data download or can reduce the spatial extent of the polygon for which data is requested and re submit the download request. Some of the datasets, such as Building outlines or Parcels for Los Angeles Region, are large datasets, and typically they require a longer processing time for downloading. If a user requests large spatial coverages and the server times-out while processing the request, please contact SSI via the feedback form, and request the data directly. When downloading raster data, note that selection of different raster data formats impose restrictions on allowed data names for downloaded data. For instance, if a user choses GRID as the data download raster format, the downloaded rasters will have an abbreviated name containing 10 characters derived from the original dataset name. If a user plans to view downloaded raster data in ArcGIS software, a geodatabase is recommended to complete this task, since it allows for longer dataset names.
Data: All of the data have been published as live map services, and therefore a user can preview all of the data by viewing the relevant map service in the integrated map viewer or in the software platform of choice (i.e., ArcMap, Google Earth or ArcGIS Explorer) before downloading. Map services are essentially maps published as a web service. One map service can contain more than one data layer. For instance, a map service Los_Angeles_Region_Contours has the following data layers: LAR_Contours_250FT; LAR_Contours_2FT; LAR_Contours_10FT; and LAR_Contours_500FT. A user can browse through various map services by accessing the Browse page of the Geoportal website. Map services are cross referenced by ISO topic categories.