Internet enabled GIS

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Internet enabled GIS

• GIS Topics and Applications
• John ReiserRowan University

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GIS as a Support System

• GIS has become a critical component in
• Land Real Estate Management
• Transportation Traffic Engineering
• Environmental Studies
• Urban Planning
• Civil Engineering
• Facilities Building Management
• Fleet Control Routing
• Mobile Location-Based Services

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Yesterday's GIS

• GIS used to be tied to the back office.
• Trade or purchase GIS data.
• Data stored on the same computer as the software.
• GIS was anchored to one place and only a select
  few had access.
• Computing is now distributed across a network
  that is accessible nearly everywhere.

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Before, data was stored on disk, on site.Now,
the data is available across the 'Net.
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Internet GIS

• Internet-enabled GIS allows professionals and the
  public a level of access to information that was
  previously impossible.
• Professionals can report on and update maps and
  data in the field.
• The public can now access plans with ease even
  contribute to the planning process via the web.

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Internet GIS

• Making GIS accessible
• Accessing data using the web
• Web Map Services (ArcIMS, WMS WFS)
• GIS servers Location-based Services
• Keyhole Markup Language (KML)
• Distributing data using the web
• Basic and advanced distribution
• Basics of generating and distributing KML
• Overview of instituting a WMS

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Data Accessibility

• We can easily share data now
• FTP
• ZIP files posted to the web
• Helps GIS users, but outsiders are left in the
  dark
• Inviting, easy to use map interfaces are the new
  way to share

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Making GIS Accessible
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NYCityMap gis.nyc.gov/doitt/nycitymap/
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Basics of Internet-enabled GIS

• Simple, open formats, usually XML based
• Data can be emailed or hosted on a webserver
• Uses a public or private GIS server for
  additional features
• KML is overlaid on top of images provided by
  Google
• Data is either geospatially aware map images, or
  actual GIS data in a web friendly format.

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Images versus Data

• Map services usually deliver images of maps that
  include information allowing software to properly
  position the image on the Earth.
• Some map services deliver map images, along with
  attribute information about the features in the
  map image.
• Other map services deliver just GIS data, leaving
  it up to the client application to render the
  data on the screen.

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Spectrum of Services
Images Only Data Only
Web Map Service
Web Feature Service
Tile Services
ArcIMS
ArcGIS
KML
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ArcGIS Server ArcIMS

• ESRI's server-side software
• Allows ArcGIS desktop mobile users access to a
  central GIS database
• Generates map images and exports feature info
• Many counties and large cities use this software
• Serves ArcGIS and web browser users
• Can also provide WMS and WFS services
• Incredibly feature rich, but expensive

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Web Map Service

• WMS is a protocol for requesting rendered map
  tiles from a GIS server
• Data returned is a map image
• Allows access to the attribute information via
  XML
• REST-ful protocol necessary info within the URL
• Open standard, free to implement

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Web Feature Service

• WFS allows for retrieval of GIS features and
  properties from a remote server
• Data is GIS features data, not maps
• WFS also allows updating GIS data on a remote
  server
• Returns XML data

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KML

• Once a "closed" language, Google pushed for its
  adoption as an open standard
• KML is a subset of XML and related to GML
• KML stores vector data along with symbology
• KML can act as a wrapper for WMS services

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Finding GIS Resources

• The Federal Government and each State maintains a
  Spatial Data Clearinghouse.
• Ours (in my opinion) is one of the best
• NJ Geographic Information Networkhttp//njgin.sta
  te.nj.us/
• Federal Geo Onestophttp//geodata.gov

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Geospatial One-Stopgeodata.gov
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NJ Geographic Information Networknjgin.state.nj.u
s
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NJGIN's Explorer

• Use Explorer to search metadata records
• Search by theme, keyword and area
• Downloads as well as live web services are
  indexed
• Provides links to connect to servers

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Information Warehousenjgin.state.nj.us
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County IMS Sites

• Several NJ counties have public ArcIMS websites
  that offer several county datasets
• None so far offer WMS services, so ArcGIS
  dependent

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Cape May County's IMScapemaycountyims.net
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ArcGIS and IMS Sites

• IMS sites can be configured to allow access using
  ArcGIS
• Most of the NJ County IMS sites are configured
  allowing access

Previously connected servers
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ArcIMS FeaturesImages and Features
Image
Features
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Accessed via a web browser
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and ArcGIS.
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Image Service allows for basic selections using
the interactive selection tools.
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Feature Service allows for selection using the
Select by Location tool.
200' from this property
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Selected features can then be exported to a
shapefile or local geodatabase.
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First Part of Lab

• Workshop

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Using KML to Enhance Your Data
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What exactly is KML?

• Keyhole Markup Language allows for an open
  exchange of GIS data, as well as
• symbology for every data element
• 3D models (COLLADA) that have been georeferenced
• camera viewpoints and tours
• network links and web services
• XML based, human readable, text format
• OGC standard open and license free

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Why KML?

• There are free shapefile viewers for Windows
  why don't we just use them?
• Shapefiles are just GIS data.
• KML allows you to define colors and icons for
  your GIS data, as well as set view points and
  include notes and links to other pages and data.
• KML gives your users access to your data,
  prepared the way you want.

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KML Basics mygeoposition.com
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KML Structure

• Unlike shapefiles, KML is not just data.
• Container format for vector data, raster data,
  network links and dynamic data.
• Data is organized into folders that can be
  rearranged and nested.

KML File
Group Layer
GIS Layer
Polygons
Image Overlay
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KML and Network Links

• KML is a relatively new format and was designed
  with the Internet in mind.
• KML supports network links, allowing remote KML
  data to be accessed on the fly.
• KML also supports WMS layers, acting as a wrapper
  for the image service.
• Lightweight files can be distributed to your
  users
• Network links guarantee that users will always
  have the latest data.

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KML Viewers

• The default data format for Google Earth is KML.
• Google Maps has some basic KML viewing capability
  paste a URL into the map search.
• ESRI's free ArcExplorer can also view KML.
• Those without GIS can easily download any of
  these free applications to view your map data.

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Google Earth

• In the workshop, you will export your data into
  KML format and view it in Google Earth.
• Google Earth provides the richest user experience
  of all the KML viewers.
• Google Earth also provides the largest library of
  GIS data.
• It doesn't mean that it's the only option many
  of the other viewers have a purpose, too!

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KML in Google Earth
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Google Maps

• Google Maps supports points, lines, polygons,
  overlays and network links in KML files.
• You can host KML, provide the link to Google
  Maps, and share your data in the same way.
• Limited by browser's capabilities most
  computers can only handle 100 features before a
  performance hit.
• Simplest way to share data to users without any
  need to install additional software.

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KML in Google Maps
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KML without ArcGIS

• If you have some GIS data
• shapefiles
• tabular (CSV with coordinates)
• or just KML you'd like hosted
• there are several websites that will convert and
  host your data as an interactive map and KML.
• One of these sites is GeoCommons.
• Another site useful for quick KML point
  generation is MyGeoPosition.

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GeoCommons geocommons.com
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GeoCommons Finder!
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GeoCommons Maker!
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Going Further

• KML is a great resource for distributing GIS
  data, but it has its limitations
• GIS specialists and developers that specialize in
  KML can help you push those limits.
• When your organization is ready to move up to a
  GIS server, you should know that there are
  several options available to you.
• Commercial and Open Source options.

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Second Part of Lab

• Workshop