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SensorWebs and Security Experiences

Dan MandlPresented at WGISS Meeting in Toulouse, FranceMay 11, 2009

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Definition

• Web Service – from Wikipedia• W3C compliant software system designed to support interoperable machin-to-

machine interaction over a network

• It communicates over the HTTP protocol used on the Web and falls generally into two categories

• Simple Object Access Protocol (SOAP)/Web Service Design Language (WSDL)• Representational State Transfer (REST)-ful

• Both need to be supported, but our preference up to this point is RESTful Web Services to reduce implementation and operations costs

Key Implementation Challenges

Web Processing

Service(WPS)

Web Coverage Service(WCS)

Sensor Planning Service

(SPS)

Organization

Orchestrating Workflow

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Secure transactions

Delegation

Single sign on

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Scope

• Web Services need to be accessible from an Open Network but are not necessarily on the NASA network

• They are used to access data and/or assets in a bi-directional manner• They may need to communicate with many communities on a permanent or

temporary basis (e.g. disaster management)• Some data to exchanged may

• Be mostly public

• Be restricted for dissemination for a specified time period (e.g no distribution rights for 60 days)

• Have license agreements

• Web security protocol needs to be easy to implement since many user will have low IT capability

• Target Web 2.0 mass market

• Implementable in less than a half a day

• Leverage existing Web 2.0 standards to lower cost and more easily gain acceptance

SensorWeb High Level Architecture

L1G

SOS

WFS

SPS

SAS

SOS

WFS

SPS

SAS

Sensor Planning Service (SPS)

Sensor Alert Service (SAS)

SensorObservation

Service (SOS)

Web Feature Service (WFS)

SensorML

Capabilities

Documents

Satellite Data Node

EO-1Satellite

In-s

itu

Sen

sor

Dat

a N

od

e

UA

V S

enso

r D

ata

No

de

SensorML

SensorML

Sa

tell

ite

s

en

so

r d

ata

pro

du

ct

Web Processing

Service(WPS)

Web Coverage Service(WCS)

Web Coordinate

Transformation Service(WCTS)

SensorML

Capabilities

Documents

DataProcessing Node

InternetSensorData Products

OpenID 2.0

RSS Feeds

floods, fires, volcanoes etc

Campaign Manager

Workflow s

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Goal is to visualize available satellite data and possible future satellite data in an area of interest and a desired time span on Google Earth.

Satellite imagery available on Myanmar flooding as a result of Nargis cyclone May 2008.

Overview

• Builds on Stefan Falke’s and Don Sullivan’s enhanced WCS in which subset of data returned based on user specified AOI and time – ESTO funded

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Federated Approach

• Build electronic trust relationships between closed communities over the open Internet

• Permanent• Temporary

• Permission policies may need to be exchanged across domains• Trust relationships must be discoverable within their community trust service

providers (layered)• E.g. Application registered with community Openid provider and thus could

check validity to see if request comes from a trusted domain as a preliminary check)

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Federated Approach Management

• Each community needs to manage its users and services in a satisfactory manner but not necessarily identically

• Provide a recognizable handle for a user or service

• Provide an accessible profile for user/service attributes

• Permission policies may need to be exchanged across domains• Local trust relationships must be discoverable by local service providers

• Some attributes may be read-write

• Privacy issues (user consent to release info)

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User & Service Profile

• Standard organization profile• Example: http://www.axschema.org/types/ (OpenID possible attributes)• One or more notification methods for delegation of authority or other

notifications (SMS, instant messages)• Roles/permission granted by organization (e.g. Red Cross representative

can task EO-1)• Some user profile attributes may be writable by outside services

• E.g. Digital Rights management/ License agreements

• Service profile (e.g client application registered so that we know it is valid)• Name, description• Main URL web page end point• RSA public key

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Secure Transactions

Data providers need to make sure that:• Message transaction has not been tampered with• Message has not been played back in tampering scheme• Message is not encrypted• Message comes in from valid service consumer• Message comes from valid user• User has proper permission to access the specified security realm• User has delegated authority to consumer (confirmation may be necessary)• User has agreed to access/license agreement

GSFC

USGS

Level 0Processing

at GSFC

First operational experiment

Experimental OpenID Provider (OP)

Server Campaign Manager

GSFC OpenID Provider (OP) Server

Other Federated OpenID Provider (OP) Servers

Server

User from GSFC

Non-GSFCUser

GSFC Domain

Non-GSFC Workflows

GSFC Workflows

GSFCUser

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NASA Considerations

• Standard trust service providers that register communities for a fee• Incommon.org

• Levels to authentication certification• Level 1 – claimed assurance• Level 2 – Identity check, user id and password• Level 3 – Increased level of identity check such as checking hard token and

2 factor personal ID• Level 4 – Fed PIC smartcard

• Method of authentication and IT security evolving• We are working with GSFC and NASA IT security team to input requirements

and for possible collaborative security prototypes