# Presentation: 676654

## The Globus Toolkit&The Handle System A Powerful Combination

**Sam X. Sun**Corporation for National Research Initiativeshttp://www.cnri.reston.va.us, http://www.handle.net**Frank Siebenlist**Argonne National Laboratorywww.globus.org

## Content

- Handle System Overview
- Grid, Globus & Handles

## CNRI & Handle System Background

- CNRI, a non-profit research organization
- R. Kahn, & R. Wilensky, "A Framework for Distributed Digital Object Services", 1995
- The National Information Infrastructure – Management layer for information sharing
- Handle System - Research project funded by US Government

## Handle System Overview

- A global name service that provides unique identifier for digital objects over the Internet
- Maintains identifiers that may be persistent over location and attribute changes
- A distributed name service for both secured name resolution and administration
- An infrastructure service that facilitates resource registry, interface discovery, and secured name-attribute binding

## Handle System Features

- Protect data integrity in name resolution, with standard mechanism for credential validation
- Distributed administration via handle system authentication protocol
- Ownership defined per handle, access control defined per handle value – independent from hosting environment
- International support via UTF-8 encoding
- Distributed service model that is both scalable and extendable

## Security Aspects of the Handle System:

- Secure name resolution: Protocol option for data integrity and confidentiality.
- Credential reference for data trustworthy
- Handle administration by individual handle owner, via handle system authentication protocol.
- Distributed ownership model: Ownership defined per handle. Access control defined per handle value.
- Supports both public key and secret key

## Handle Namespace

- _Syntax Definition:_
- 	<handle> 	::= <NA> / <Local-Name>
- 	<NA>	::= *(<na_seg> ) <na segment>
- 	<na_seg> 	::= Any Unicode 2.0 character encoded in UTF-		     8, except ‘/’ and ‘.’
- 	<Local-Name> ::= Any Unicode 2.0 character

- _Examples:_
- 		10.123/456
**	****	**cnri.dlib/july95-arms

## Example: Handle and Handle Values

- Handle

- Index

- Data Type

**10.123/456**

**2**

**URL**

**http:/srv1.pub.com/...**

## Handle System Data Model

- Access control for the handle value

- May contain references of digital signatures/certificates

## Handle Administrator Record

## Handle System Protocol: Message Structure

## Handle Resolution

**GHR**

## Handle Clients

- Handle System

- http://hdl.handle.net/123.456/abc

## Handle Clients

- Handle System

- hdl:/123.456/abc

**Client**
**Plug-In**

## Handle Clients

- Handle System

**HTTP**

**Handle Admin API**

## Handle Clients

- Handle System

**Custom**
**Client**

## Handle System References:

-  Handle System Namespace and Service Definition  (RFC3651)
-  Handle System Protocol Specification (RFC3652)
-  Handle Server Administration Manual (HTML)_[http://www.handle.net/software](http://www.handle.net/software)_

## Development Resources:

- Open source license on handle server implementation and client libraries

- Client library available in Java, C, Python, and Perl

- Server implementation in Java. C-version server implementation in progress.

- Caching and Proxy server implementation in Java

- Handle Plug-in for Internet browser and Adobe Reader

## Use of Handle System:

- Persistent naming and service reference
- Metadata registration and management
- Identity and Key Management
- Grid Computing: WS-resource attribute
- Internet Digital Rights Management (IDRM)
- P2P computing and resource sharing

## Handle System Initiatives

- Library of Congress
- DTIC (Defense Technical Information Center)
- IDF (International DOI Foundation)
- CrossRef (scholarly journal consortium)
- Enpia (Korean content management technology firm)
- CDI (U.S. content management technology firm)
- LON (U.S. learning object technology firm)
- CAL (Copyright Agency Ltd  - Australia)
- TSO (U.K. publisher & info mgmt service provider)
- MEDRA (Multilingual European DOI Registration Agency)
- Nielsen BookData (bibliographic data - ISBN)
- R.R. Bowker (bibliographic data - ISBN)
- Office of Publications of the European Community (applied)
- NTIS (National Technical Information Service)
- DSpace (MIT + HP)
- Various digital library production and research projects

## Content

- Handle System Overview
- Grid, Globus & Handles

## Handle System, OGSA and Globus

- Grid Resource, State & Handles
- Grid, Virtualization & Handles
- Resource’s Endpoint Stability
- “External” Resource Properties
- Futures & Demo

## The Grid Resource

- The Grid “Resource”
-  Application, Job, ...
-  DB-record, disk drive, CPU-load
-  File, file-fragment, virtual piece of data
-  Contract, negotiation state, observed policy
-  Resource is “state”...
- Very much like distributed “Objects”
-  Grid Resource accessed through Web Service
-  Web Service is resource’s “hosting environment”

## The Grid: Virtualization

- Virtualization of Resources
- Computers, applications, jobs, locations, files, file-fragments, ???
- Virtualization is about
- Raising abstraction level
- Transparently changing under the covers
- Not caring what’s under the cover
- ...
- Adding levels of indirection
-   **Virtualization = Handles**

## The Grid Resource “Stability”

- Web Service + Resource = “Network Pointer” to state
- WebService Resource Framework: “Endpoint Reference”
- Web Service + Resource “instability”
-  multiple access methods
-  network address may change
-  resource may move
- Web Service + Resource: Unique Identifier
-  Stable “name” for policy, audit, comparison, “reasoning”
- Web Service + Resource: Network Pointer
-  Hosting environment recycling => different port number
-  Resource moves => new network pointer
-  Stable “handle” resolves to new network pointer
- Need Handle concept for stability
- “WSRF Renewable Reference” ???

## Service Migration

- Hosting Environment B

- ResourceId

- ...

- hdl:1.2/abc

- ...

- EPR

- ...

- <ws-addr>

- ...

- Service

- Hosting Environment A

- Requester

- HandleResolver

- ResourceId

- hdl:1.2/abc

- EPR

- <ws-addr>

- Service Locator

## Service Instance Migration and Security

- Identity/Key “normally” associated with hosting environment and not with Instance
- Moving instance => change of secure identity
- What about policies for that instance?
- Users that were allowed to access, can they still access moved instance?
- Hosting environment able to override (?)
- Where to maintain policy info?
- Maybe in same naming/registry svc?
- Move with instance state?
- Need more real-world requirements...
- Learn from mobile agent systems...
- No “real” efforts yet at GGF.

## WSRF Resource Properties & Handles

- Handle System

- http://hdl.handle.net/123.456/abc

## WS-Handle Proxy Server

- WSRF Relying Party

- Handle Server “World”

- WS-Handle
- Proxy Server

- Lookup or registration of “name”
- Notification registration of change

- Translation/mapping of “name” to handle

- Handles securely stored/retrieved/replicated/globally-located

- Proxy approach needed
- for any implementation
- (handle/ldap/rdbms)
- =>
- base choice on merits
- of back-end system

## The Globus Toolkit & Handle System

- WSRF has “identified” need for EPR stability
- Clearly requirement for more sophistication
-  load-balancing, fail-over, resource migration
-  “external” resource properties
-  dynamic policy decoration
-  virtualization as a concept requires indirection
- Natural Synergy between GT and Handle System!
-  Recognized by both Globus Alliance and CNRI
**We’re working to make this vision a reality:**
**Come and see the DEMO (3:30pm)!**

## Service Migration

- Hosting Environment B

- ResourceId

- ...

- hdl:1.2/abc

- ...

- EPR

- ...

- <ws-addr>

- ...

- Service

- Hosting Environment A

- Requester

- HandleResolver

- ResourceId

- hdl:1.2/abc

- EPR

- <ws-addr>

- Service Locator