Datasets:

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Geographical Information GIS means ““Geographical Information ÑÑ GIS means System”” System Its called that because there is information ÓÓ Its called that because there is information behind the map. behind the map.

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GIS vs CAD GIS vs CAD

Difference between mapping software or CAD and GIS: Difference between mapping software or CAD and GIS:

CAD CAD

Mapping 2D or 3D geospatial data ÓÓ Mapping 2D or 3D geospatial data

GISGIS Three levels of GIS applications: ÑÑThree levels of GIS applications: Inventory (What is there?) ÓÓ Inventory (What is there?) Analysis (Answering questions) ÓÓ Analysis (Answering questions) Shortest distance ÔÔ Shortest distance

Modeling (Making predictions) ÓÓ Modeling (Making predictions)

CAD stands for Computer-Aided Design

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A GIS is a software system that connects map layers with tables of information.

GIS MAP

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Importance of Geographic Data Importance of Geographic Data

GIS is different than most applications ÑÑ GIS is different than most applications

Word processing, Spreadsheets…… are are ÑÑ Word processing, Spreadsheets entirely dependent on input of YOUR entirely dependent on input of

YOUR datadata

GIS users nearly always require reference ÑÑ GIS users nearly always require reference map data (e.g., streets, boundaries) that are map data (e.g., streets, boundaries) that are by others maintained by others maintained

As GIS users, we rely heavily on ÑÑ As GIS users, we rely heavily on data sources external”” data sources ““external

Data has to be shared

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Evolution of Data Sharing Evolution of Data Sharing

Distributed GIS Distributed GIS (via web services) (via web services)

Downloading Downloading DataData

y t i r u t a M

Media Media Distribution Distribution ((““ftpftp””))

Shared Shared Diskspace Diskspace

Time

Issues with typical/traditional Data Issues with typical/traditional Data Sharing Methods Sharing Methods

Getting all the data ÑÑ Getting all the data Vintage ÑÑ Vintage Format ÑÑ Format Coordinate System/Projection ÑÑ Coordinate System/Projection Media Compatibility ÑÑ Media Compatibility File Size ÑÑ File Size Bandwidth ÑÑ Bandwidth Metadata Distribution ÑÑ Metadata Distribution

Typically requires data manipulation prior to use (reformatting, reprojecting, clipping, etc.)

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Distributed GIS Model Distributed GIS Model NYS DEC NYS CSCIC USGS

US EPA

DEM

Wetlands

Orthos

Real-time access to geographic data and services

Local Data

Virtually Any Client

Mashup Mashup

An application that combines data from multiple sources ÑÑ An application that combines data from multiple sources content aggregation”” Referred to as ““content aggregation ÑÑ Referred to as Combines similar ÑÑ Combines systems/services different systems/services different Term originated from music industry when a new song ÑÑ Term originated from music industry when a new song was made from several existing tracks was made from several existing tracks

types of data (e.g., maps,) from similar types of data (e.g., maps,) from

Distributed GIS Advantages Distributed GIS Advantages

Format is irrelevant ÑÑ Format is irrelevant Guarantees latest data ÑÑ Guarantees latest data No media involved ÑÑ No media involved Size is irrelevant (only requested ÑÑ Size is irrelevant (only requested data needed) data needed) Software independent ÑÑ Software independent

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Distributed GIS Advantages Distributed GIS Advantages

Device independent (PC, phone) ÑÑ Device independent (PC, phone) Saves Time! ÑÑ Saves Time! Data security ÑÑ Data security Only view data ÓÓ Only view data Download data ÓÓ Download data Data upload and editing ÓÓ Data upload and editing

Distributed GIS Advantages Distributed GIS Advantages Desktop software's also support WMS ÑÑ Desktop software's also support WMS ÓÓ QGISQGIS ArcGIS ÓÓ ArcGIS

Advantages ÓÓ Advantages Carryout advance GIS operations on the data. ÔÔ Carryout advance GIS operations on the data. Use as source data for GIS analysis. ÔÔ Use as source data for GIS analysis. Easy to search and access data. ÔÔ Easy to search and access data.

Distributed GIS Disadvantages Distributed GIS Disadvantages

Dependent on server availability ÑÑ Dependent on server availability Dependent on internet availability ÑÑ Dependent on internet availability Users need to be aware of web service ÑÑ Users need to be aware of web service

Service Oriented Service Oriented Architecture Architecture

Architecture that is based on integrating ÑÑ Architecture that is based on integrating , interoperable services loosely coupled””, interoperable services ““loosely coupled

Loosely coupled means NOT physically ÑÑ Loosely coupled means NOT physically bound or compiled like an EXE or DLL bound or compiled like an EXE or DLL

These services can be invoked and ÑÑ These services can be invoked and consumed remotely over a network consumed remotely over a network

Data and messages are exchanged ÑÑ Data and messages are exchanged between clients and services between clients and services

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Basic Web Page Operation Basic Web Page Operation

Request

Response (HTML document)

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Web Service Operation Web Service Operation

Client

Convert UTM To Lat/Long

Zone: 18 Longitude: -73.3456 Processing…. Easting: 623,456.3 Latitude: 42.2753 Northing: 4,745,342.3

Creates XML Request
Request sent to web service

Web Server (Listening for requests)

Receives response and parses
Response sent to client
Receives request and parses XML
Calls the function
Creates response XML with results

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Types of Geospatial Web Services Types of Geospatial Web Services

Map/Data Oriented Services ÑÑ Map/Data Oriented Services Map Services (Image) ÓÓ Map Services (Image) Feature Services (Vector) ÓÓ Feature Services (Vector) Coverage Services (Grid) ÓÓ Coverage Services (Grid)

Task Oriented Services ÑÑ Task Oriented Services Routing Services ÓÓ Routing Services Geoprocessing Services ÓÓ Geoprocessing Services

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Map Services Map Services

ÑÑ Client requests a map from a server for a specified geographic e

xtent Client requests a map from a server for a specified geographic extent

Map Server renders the requested map internally and converts to an an ÑÑ Map Server renders the requested map internally and converts to image file (e.g., JPG, PNG, GIF) and returns the map image to the e image file (e.g., JPG, PNG, GIF) and returns the map image to th client for display client for display

Fast map display is possible. ÑÑ Fast map display is possible.

99% of current activity's in Web GIS Map/Image Serving

made way for WebGIS popularity Google Map”” made way for WebGIS popularity ““Google Map

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Map Service Operation Map Service Operation

Client

Web Server/Map Server

Creates XML Request
Request sent to web service
Receives response, parses to extract image and updates map
Response sent to client
Receives request and parses XML
Calls the map server to request map
Map Server generates map as image file
Creates response XML with image file

Sample site Sample site

http://www.wunderground.com/radar/map.as ÑÑ http://www.wunderground.com/radar/map.as pp http://maps.eyesontheforest.or.id/ ÑÑ http://maps.eyesontheforest.or.id/ https://mapsengine.google.com/map ÑÑ https://mapsengine.google.com/map

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Need for standardization Need for standardization

Every one was creating own standards ÑÑ Every one was creating own standards Google maps ÓÓ Google maps Bing Maps ÓÓ Bing Maps USGS ÓÓ USGS

Make universal data sharing possible. ÑÑ Make universal data sharing possible. Overcome technical chalengers. ÑÑ Overcome technical chalengers. Make way for rapid development in ÑÑ Make way for rapid development in WebGIS. WebGIS.

OGC and Open Web Mapping OGC and Open Web Mapping

ÑÑ The The Open Geospatial Consortium (OGC) was founded in 1994 Open Geospatial Consortium (OGC) was founded in 1994 An international consortium of 346 organizations that lead the ÑÑ An international consortium of 346 organizations that lead the development of open standards and specifications to enable the development of open standards and specifications to enable the interoperability of geospatial and location based services interoperability of geospatial and location based services

ÑÑ They have developed a series of open standards for geospatial we

They have developed a series of open standards for geospatial web b services such as: services such as: Geography Markup Language (GML) ÓÓ Geography Markup Language (GML) Web Mapping Services (WMS) ÓÓ Web Mapping Services (WMS) Web Feature Services (WFS) ÓÓ Web Feature Services (WFS) Web Coverage Services (WCS) ÓÓ Web Coverage Services (WCS) Referrred to as ““OpenGIS

OpenGIS®®”” standards standards

ÑÑ Referrred to as

OGC Web Services (OWS) OGC Web Services (OWS) Web Map Service (WMS) ÑÑ Web Map Service (WMS) ÓÓ Web Map Service Interface Standard (WMS) provides a simple HTTP

Web Map Service Interface Standard (WMS) provides a simple HTTP interface for interface for requesting geo--registered map images from one or more distributed geospatial registered map images from one or more distributed geospatial requesting geo databases. A WMS request defines the geographic layer(s) and area of interest to a of interest to databases. A WMS request defines the geographic layer(s) and are be processed. The response to the request is one or more geo--registered map registered map be processed. The response to the request is one or more geo rowser images (returned as JPEG, PNG, etc) that can be displayed in a browser images (returned as JPEG, PNG, etc) that can be displayed in a b application. application.

Web Feature Service (WFS) ÑÑ Web Feature Service (WFS) ÓÓ The WFS operations support INSERT, UPDATE, DELETE, LOCK, QUERY a

The WFS operations support INSERT, UPDATE, DELETE, LOCK, QUERY and nd stributed DISCOVERY operations on geographic features using HTTP as the distributed DISCOVERY operations on geographic features using HTTP as the di computing platform. It is the function of a web feature service, in its interaction with in its interaction with computing platform. It is the function of a web feature service, ensure that changes the data storage system used to persistently store features, to ensure that changes the data storage system used to persistently store features, to to data are consistent. to data are consistent.

Web Coverage Service (WCS) ÑÑ Web Coverage Service (WCS) ÓÓ The OpenGIS

The OpenGIS®® Web Coverage Service Interface Standard (WCS) defines a Web Coverage Service Interface Standard (WCS) defines a standard interface and operations that enables interoperable access to geospatial ess to geospatial standard interface and operations that enables interoperable acc "grid term [http://www.opengeospatial.org/ogc/glossary/c]. The "coverages" "coverages" "grid term [http://www.opengeospatial.org/ogc/glossary/c]. The digital aerial photos, coverages" typically refers to content such as satellite images, digital aerial photos, coverages" typically refers to content such as satellite images, s at each digital elevation data, and other phenomena represented by values at each digital elevation data, and other phenomena represented by value measurement point. measurement point.

Web Mapping Services (WMS) Web Mapping Services (WMS)

WMS is the OGC specification for ÑÑ WMS is the OGC specification for implementing a map (image) service implementing a map (image) service

Does not allow for cached map services ÑÑ Does not allow for cached map services

WMS provides 3 functions for clients to ÑÑ WMS provides 3 functions for clients to access functionality access functionality

Two functions are mandatory to be ÑÑ Two functions are mandatory to be implemented, the third function is implemented, the third function is optional optional

ÑÑ This results in two general

This results in two general ““types WMS Services WMS Services ÓÓ BasicBasic Queryable ÓÓ Queryable

types”” of of

Web Mapping Services Web Mapping Services (WMS) (WMS)

Basic WMS Service Basic WMS Service Every WMS service MUST support the following two functions: Every WMS service MUST support the following two functions:

ÓÓ GetCapabilities

Describes the capabilities and available layers GetCapabilities –– Describes the capabilities and available layers

ÓÓ GetMap

Generates a map image based on input parameters GetMap –– Generates a map image based on input parameters

Queryable WMS Service Queryable WMS Service The following function is optional for WMS services: The following function is optional for WMS services:

ÓÓ GetFeatureInfo

Gets the attributes for a specified feature GetFeatureInfo –– Gets the attributes for a specified feature

http://www.opengeospatial.org/standards/wms http://www.opengeospatial.org/standards/wms

What can be done with a What can be done with a WMS service? WMS service?

ÑÑ Each client application (e.g., ArcView, MapInfo, Google Earth, e

Each client application (e.g., ArcView, MapInfo, Google Earth, etc.) tc.) handles WMS services differently handles WMS services differently

However, generally the following functions are available: ÑÑ However, generally the following functions are available: Map Display and navigation ÓÓ Map Display and navigation Zoom to layer ÓÓ Zoom to layer Layer Control ÓÓ Layer Control Identify feature (only with Queryable Map services) ÓÓ Identify feature (only with Queryable Map services)

Anything else is not available ÑÑ Anything else is not available No feature selection ÓÓ No feature selection No geoprocessing ÓÓ No geoprocessing No attribute table/browser display ÓÓ No attribute table/browser display Menus/Buttons are greyed out and disabled ÓÓ Menus/Buttons are greyed out and disabled

WebGIS Components WebGIS Components

Web GIS Components (Cont …………)) Web GIS Components (Cont

Internet Browser such as Internet Explore, Mozila firefox Internet Browser such as Internet Explore, Mozila firefox

••Client: Client: –– etcetc Internet Connection: ••Internet Connection:

–– Performance of a web mapping site largely depends on Performance of a web mapping site largely depends on bandwidth of the Internet connection the bandwidth of the Internet connection the Higher the bandwidth better the performance –– Higher the bandwidth better the performance

Web server ••Web server

Handle the requests from Web Browser (user) and Handle the requests from Web Browser (user) and

–– Return the web page Return the web page Apache,IIS –– Apache,IIS

Meta Data ••Meta Data

–– ––

data about data data about data Including Server URL, Owner etc Including Server URL, Owner etc

Web GIS Components (Cont …………)) Web GIS Components (Cont

Map Server ••Map Server

–– page. page. ––

TheMapServer is the engine behind the maps you see on a web TheMapServer is the engine behind the maps you see on a web

The Map Server needs to be configured to communicate between The Map Server needs to be configured to communicate between the web server and assemble data layers into an appropriate the web server and assemble data layers into an appropriate

image. image.

Map viewer ••Map viewer

–– ––

Renders the maps on the client side Renders the maps on the client side The relationships among Objects The relationships among Objects ––Map Extent Map Extent Map Size ––Map Size Reference Map (Key Map) ––Reference Map (Key Map)

Point Map Server where to locate data Point Map Server where to locate data Define how things are to be drawn Define how things are to be drawn

Colors ––Colors Labeling etc…… ––Labeling etc

WEB GIS Software WEB GIS Software

Category

Commercial

Operating Systems

Windows

Free

Linux

Database SW

ORACLE , MSsql

Mysql , Postgresql

Spatial Database SW

ORACLE Spatial

MySQL Spatial, PostGIS

RS\GIS Applications

ArcGIS, ERDAS, ENVI

ILWIS, GRASS, QGIS

Web GIS Applications

ArcIMS

MapServer, GeoServer

ArcGIS Server/ ArcSDE

Mapbender, OpenLayers

GIS components Open WEB--GIS components Open WEB

Map Servers

Rendering spatial data (maps, images,

and vector data) for the web

• Minnesota MapServer • GeoServer

Map Viewer

http://mapserver.org/

http://geoserver.org

It provides a data model and web based interfaces for displaying, navigating and querying OGC compliant map services

www.mapbender.org/

• Mapbender • OpenLayers

openlayers.org/

WebGIS using open source tools WebGIS using open source tools

Example: The following WebGIS application was developed using GeoServer & OpenLayers

Open Web GIS solutions Open Web GIS solutions

GeoNode GeoNode based application and platform for GeoNode is a web--based application and platform for ÑÑGeoNode is a web developing geospatial information systems (GIS) and for developing geospatial information systems (GIS) and for deploying spatial data infrastructures (SDI). deploying spatial data infrastructures (SDI).

geonode.org/

GeoNetwork opensource GeoNetwork opensource GeoNetwork is a catalog application to manage spatially ÑÑGeoNetwork is a catalog application to manage spatially referenced resources. It provides powerful metadata editing and referenced resources. It provides powerful metadata editing and search functions as well as an embedded interactive web map search functions as well as an embedded interactive web map viewer. It is currently used in numerous Spatial Data viewer. It is currently used in numerous Spatial Data Infrastructure initiatives across the world. Infrastructure initiatives across the world.

http://geonetwork-opensource.org/

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Core components Core components

• Upload Vector & Raster data • Metadata support. • Create Maps • Print maps as pdf

• Up- and downloading data,

graphics, documents, pdf files

• Online editing of metadata • Scheduled harvesting and

synchronization of metadata • Support for OGC-CSW 2.0.2 ISO

Profile, OAI-PMH, Z39.50 protocols.

Web Server

Map Viewer

GeoEDGE GeoEDGE

Compilation of Free Open source Web GIS Compilation of Free Open source Web GIS resources Powerful tool that support resources Powerful tool that support

Map services ÓÓ Map services GIS spatial operations ÓÓ GIS spatial operations Map display ÓÓ Map display Advance Spatial analysis ÓÓ Advance Spatial analysis Automatic Geocoding ÓÓ Automatic Geocoding Geo reference map views ÓÓ Geo reference map views Interactive multi user digitizing ÓÓ Interactive multi user digitizing

Web Processing Services

Web Processing Service Web Processing Service

ÑÑ The OpenGIS

The OpenGIS®® Web Processing Service (WPS) Interface Standard provides Web Processing Service (WPS) Interface Standard provides ponses) for rules for standardizing how inputs and outputs (requests and responses) for rules for standardizing how inputs and outputs (requests and res geospatial processing services, such as polygon overlay. . geospatial processing services, such as polygon overlay

of a The standard also defines how a client can request the execution of a ÑÑ The standard also defines how a client can request the execution nes an process, and how the output from the process is handled. It defines an process, and how the output from the process is handled. It defi s and clients’’ interface that facilitates the publishing of geospatial processes and clients interface that facilitates the publishing of geospatial processe y the WPS discovery of and binding to those processes. The data required by the WPS discovery of and binding to those processes. The data required b e server. can be delivered across a network or they can be available at the server. can be delivered across a network or they can be available at th

WPSWPS Advantages Advantages

GIS Operation online ÓÓ GIS Operation online No need of GIS applications ÓÓ No need of GIS applications Easy to use ÓÓ Easy to use No need of GIS knowledge ÓÓ No need of GIS knowledge Can be done on any device ( mobile / pc) ÓÓ Can be done on any device ( mobile / pc)

Disadvantages Disadvantages

Need powerful server ÓÓ Need powerful server

Thank You Thank You

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