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Interacting with NDG

Interacting with NDG. Bryan Lawrence (on behalf of a big team). +. +. ]=. +[. +. +. BADC, BODC, CCLRC, PML and SOC. No one would change their data storage systems! Need to support a wide range of “metadata-maturity”! No NDG-wide user management system possible.

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Interacting with NDG

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  1. Interacting with NDG Bryan Lawrence (on behalf of a big team) + + ]= +[ + + BADC, BODC, CCLRC, PML and SOC

  2. No one would change their data storage systems! Need to support a wide range of “metadata-maturity”! No NDG-wide user management system possible. It is illegal to share user information without each and every user agreeing … implies no way of having one virtual organisation with common user management! With a large enough group it is impossible to agree on common roles that could be associated with access control. … but we want single-sign on … and trust relationships between data providers … NDG Assumptions

  3. Integration familiarity • NDG Use cases • Discovery (D) • Find things • Context (B) • Know what they represent • Manipulation (A) • Do useful things with them • NDG-Lite • NDG Discovery • Local Systems • Find things, read web pages … • Use data provider internal systems to access data etc.

  4. Discovery Only Requirement for properly formatted discovery metadata DIF now ISO19139 later ISO19139 issues. OAI repository Decision on “harvestability” … Must be kept live … Related URLs and Services Decisions on binding and service metadata outstanding! Deployment of NDG discovery service at provider websites Branding Maintenance Start NOW! Levels of Engagement: (1) NDG-Lite

  5. Discovery + “A” services Need to deploy NDG security (of which more later) At the moment, need to have CSML data descriptions and to deploy the NDG data extractor (but not necessarily GEOSPLAT). In the future we may have “vanilla” OGC services … In the future may use “OWN” feature definitions … Expecting to support: NetCDF, NasaAmes, GRIB, HDF(4 or 5 not yet clear), SQL queries, xquery extractions. Probably not something to be taken on before mid-2007! Levels of Engagement: (2) NDG-Data (only) Providers

  6. We only expect data centres to engage in the time and expense of producing browse metadata! MOLES is/will be a coat-hanger for discipline specific metadata, with some holes for common concepts. We will provide tooling for a MOLES repository to autogenerate discovery metadata (one less job to do!) Provides the basis for cross-data centre thematic repositories (e.g. RAPID) Can be secure metadata in own right! Levels of Engagement (3): Data Centres and Browse

  7. Clean separation between concepts: Authentication Identity - Who you are Users are identified between data providers and services by means of Proxy Certificates Proxy Certificates issued by MyProxy services Users are identified between sessions at the same browser by means of a cookie which points to the location of a proxy certificate. Authorisation For a user: what you can do e.g. what data they can access For a data provider: how you determine what a user can and can’t do NDG Attribute Certificates determine access Attribute Certificates issued by AttributeAuthorities. Authentication and Authorisation

  8. Controlling Access to Data • NDG Attribute Certificate • Issued to a user by an ATTRIBUTE-AUTHORITY • Contain roles – these determine what the user is authorised to do • An attribute authority determines on behalf of a data provider what roles a user has, from the list of roles known to that data provider • e.g. badc has the coapec role which allows access to the coapec data set. If a badc user has a badc issued Attribute Certificate containing coapec then badc will grant access. • XML based • Issued by the Attribute Authorities on receipt of a valid user Proxy Certificate • Digitally signed by the Attribute Authority issuer • Contain the user’s identity expressed as a Distinguished Name as derived from the user’s Proxy Certificate • Has a timebound validity

  9. All data providers deploy, or have access to, a myproxy database capable of delivering proxy certificates on request. All data providers deploy or have access to a Session Manager instance. No requirement for the myproxy to visible outside a firewall, access can be mediated by a Session Manager. All data providers secure resources by coupling resources to roles. There is no assumption that data providers share the same role names or role definitions. All data providers deploy, or have access to, Attribute Authorities that grant NDG Attribute Certificates to users based on their “rights”. Key Concepts thus far

  10. <?xml version="1.0" encoding="utf-8"?> <AAmap> <thisHost name="BADC"> <wsdl>badcAttAuthorityURI</wsdl> <loginURI>badcLoginPageURI</loginURI> </thisHost> <trusted name="BODC"> <wsdl>bodcAttAuthorityURI</wsdl> <loginURI>bodcLoginPageURI</loginURI> <role remote="aBODCrole" local="aLocalRole"/> </trusted> <trusted name="escience"> <wsdl>eScienceAttAuthorityURI</wsdl> <role remote="anEScienceRole" local="anotherLocalRole"/> </trusted> </AAmap> HANDLES AUTHORISATION HANDLES AUTHENTICATION LIST OF REMOTE ADDRESSES FOR GETTING AUTHORISATION CREDENTIALS AUTHORISATION Example MapConfig TRUST Trust between data providers is established by making BILATERAL agreements on role mapping!

  11. AA Client Application smClient User Authorisation • UserSession • CredWallet SessionManager WS sessionID and smWSDL reqRole AAwsdl ProxyCert, reqAttCert AttCert (Installable Library) Returned Proxy Cert. is kept in CredWallet of user’s UserSession instance Calls FIREWALL Exploits reqAuthorisaton method Local smClient talks to local SessionManager which may or may not talk to remote SessionManagers. Credential Wallet is populated with attribute certificates as needed.

  12. What’s needed to represent ID? [User DataBase of some sort and Own connection software] [PKI/Proxy Certificates] [MyProxy Server] [Session Manager] What’s needed to grant access rights to a user? [Attribute Authority] [Session Manager] Some “database” binding resources to roles and AA How to Deploy a system [Indicate that a minimally configured data provider can use remote resources to provide these services]

  13. Python Browser Application class YourClass: ''' Dummy class encapsulating key ndg security concepts from a browser application developers perspective ''' def __init__(self,stuff): ... self.cookie=... #set cookie self.config=... #read from config file, includes local smWSDL …. self.makeGateway() ... def makeGateway(self,cookie=None): ''' Make connection to NDG security and load what is necessary for an NDG cookie to be written ''' # - the requestURL so that a redirect can come back, and to pass # any URL components which have come back from one ... # - your local smWSDL address, and your cookie ... self.ndgGate=securityGateway(self.requestURL,self.cookie,self.config) def goforit(self): ''' your actions ... trying to access a URI for which you may have constraints''' ... if constraints.exist: result=self.ndgGate.check((role,AAwsdl)) if result=='AccessGranted': access=1 else: access=0

  14. Vocab Services Users NDG GUI Interface(s) Data Providers NDG Core Services Architecture: Deployment

  15. Vocab Services Users NDG GUI Interface(s) NDG Core Services Architecture: Deployment

  16. Vocab Services Users NDG GUI Interface(s) Architecture: Deployment

  17. Vocab Services Users Architecture: Deployment

  18. Architecture: Deployment

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