Handle System Overview Larry Lannom Corporation for National Research Initiatives

Handle System Overview

Larry Lannom

Corporation for National Research Initiativeshttp://www.cnri.reston.va.us/

http://www.handle.net/

Corporation for National Research Initiatives

• Framework for managing Digital (Information) Objects

• Give it a name and talk to it– Don’t worry about where it is– Don’t worry about what it’s made of

• Rise above details of application versions and content formats

Digital Object Architecture - Goals


Digital Object Architecture

Client

Resource Discovery

•Search Engines•Metadata Databases•Catalogues, Guides, etc.

Resolution System

Repositories / Collections


Digital Object Architecture ComponentsHandle System

• Go from name to attributes

• Fundamental indirection system for Digital Object management on the net

• No free lunch– Added layer of infrastructure– Must be managed


Digital Object Architecture ComponentsRepository

• Frees digital content from constraints of specific technologies

• Provide access across systems, space, time

• No free lunch– Added layer of infrastructure– Must be managed


Repository Approach to Interoperability

• Modularization– Separate raw data (byte stream) from data type– Separate type definition from type

implementation

• Extensibility– Create new types on demand– New components accessible (with controls)

over the network

• Standard access protocol (RAP)

Naming Resources on the Net

The Problem

Internet

chapter.pdfwww.acme.com

Internet


The Solution

Name = Value(s)10.123/xyz = http://www.acme.com/chapter.pdf

Naming Service

http://www.acme.com/chapter.pdfwww.acme.com

Internet


The Solution

Name = Value(s)10.123/xyz = http://www.newbusiness.com/chapter.pdf

http://www.newbusiness.com/chapter.pdf

Naming Service

www.newbusiness.com

www.acme.com


• Distributed, scalable, secure• Enforces unique names• Enables association of one or more typed values,

e.g., URL, with each name• Optimized for speed and reliability• Open, well-defined protocol and data model• Provides infrastructure for application domains,

e.g., digital libraries, electronic publishing ...

CNRI Handle System


Handle System Implementations

• Library of Congress

• 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)

• cIDF (Content IDF Forum, based in Japan)

• DTIC (Defense Technical Information Center)

• NTIS (National Technical Information Service)

• Various digital library production and research projects


Handles Resolve to Typed Data

URL 2 http://a-books.com/….

DLS 9 acme/repository

HS_ADMIN 100 acme.admin/jsmith

XYZ 100111001111012

Handle dataHandle Data typeIndex

10.123/456 URL 1 http://acme.com/….

The Two Types of Handle Query

Give me all data associated with handle 10.1000/123.

1. Request all data

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

HandleClient

3251094

10.1000/123 URL1(Server in US)URL2 (Server in Asia)URL3 (Server in Europe)public keyemail addressrights data

URLURLURLPKEMIP

Index Type DataHandle

Give me all data of type URL associated with handle 10.1000/123.

2. Request all data of a given type

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

HandleClient

325

10.1000/123 URL1(Server in US)URL2 (Server in Asia)URL3 (Server in Europe)

URLURLURL

Index Type DataHandle

Handle Resolution

is a collection ofhandle services,each of which consists of one ormore replicated sites,

Site 1Site 1 Site 2Site 2

Site 1Site 1

Site 2Site 2

Site 3Site 3 …... Site nSite n

Client

The Handle System

LHS

LHS LHS

LHSGHR

each of which mayhave one or moreservers.

123.456/abc URL 4 http://www.acme.com/

http://www.ideal.com/8URL

#1#1 #2#2 #n#n#4#4#3#3

#1#1 #2#2

...

Handle Clients

Global HandleRegistry

1. Sends request to Global to resolve 0.NA/10.1000 (naming authority handle for 10.1000)

Client

Request to Client:Resolve hdl:10.1000/1

Handle Clients

Client



2. Global Responds withService Information for 10.1000

Service InformationAcme Local Handle Service

xcccxv xc xc xc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

..

..

..

xcxcxc

..

..

..

xcxcxc

..

..

..

...

xcccxvxccxxccx

xcccxvxccxxccx

xcccxvxccxxccx

Service Information - Acme Local Handle Service

Primary Site

123.45.67.8

Port #

Secondary Site B

Server 1

Server 1

Server 2

Server 3

Server 1

Server 2 123.52.67.9

321.54.678.12

321.54.678.14

762.34.1.1

123.45.67.4

Public Key ...

2641

K03RLQ...

2641

2641

2641

2641

2641

5&M#FG...

F^*JLS...

3E$T%...

A2S4D...

N0L8H7...

...

...

...

...

...

...

IP Address

Secondary Site A

xcccxv xc xc xc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

..

..

..

xcxcxc

..

..

..

xcxcxc

..

..

..

...

xcccxvxccxxccx

xcccxvxccxxccx

xcccxvxccxxccx

Handle Clients


Primary Site

123.45.67.8

Port #

Secondary Site B

Server 1

Server 1

Server 2

Server 3

Server 1

Server 2 123.52.67.9

321.54.678.12

321.54.678.14

762.34.1.1

123.45.67.4

Public Key ...

2641

K03RLQ...

2641

2641

2641

2641

2641

5&M#FG...

F^*JLS...

3E$T%...

A2S4D...

N0L8H7...

...

...

...

...

...

...

IP Address

Secondary Site A

xcccxv xc xc xc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

..

..

..

xcxcxc

..

..

..

xcxcxc

..

..

..

...

xcccxvxccxxccx

xcccxvxccxxccx

xcccxvxccxxccx

Handle Clients


Primary Site

123.45.67.8

Port #

Secondary Site B

Server 1

Server 1

Server 2

Server 3

Server 1

Server 2 123.52.67.9

321.54.678.12

321.54.678.14

762.34.1.1

123.45.67.4

Public Key ...

2641

K03RLQ...

2641

2641

2641

2641

2641

5&M#FG...

F^*JLS...

3E$T%...

A2S4D...

N0L8H7...

...

...

...

...

...

...

IP Address

Secondary Site A

xcccxv xc xc xc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

xcxcxc

..

..

..

xcxcxc

..

..

..

xcxcxc

..

..

..

...

xcccxvxccxxccx

xcccxvxccxxccx

xcccxvxccxxccx

Handle Clients

Handle Clients

3. Client queries Server 3 in Secondary Site A for 10.1000/1Client


#1#1 #2#2

#1#1

#1#1#2#2

#3#3Primary Site

Secondary Site A

Secondary Site B


Acme LocalHandle Service

Handle Clients

4. Server responds with handle data

Client


#1#1 #2#2

#1#1

#1#1#2#2

Primary Site

Secondary Site A

Secondary Site B


#3#3

Acme LocalHandle Service

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

Web ClientHandle Administration

Client

ResolveHandle

HTTP Redirect

Proxy/Web Server

HTTP Get

Handle Data

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

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

ClientHandle Administration

Client

hdl:/123.456/abc

ClientPlug-In

Resolve HandleRequest

Handle Data

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

WebHandle Administration

Client

Web Server

HTTP

Handle Admin API

Admin Forms

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

WebHandle Administration

Client

CustomClient

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System

Handle Administrationembedded in another

process


processWeb

Handle Clients

LHS

LHS LHS LHS

LHS

LHS

LHS

LHSGHR

LHS

Handle System


process


process

Handle Resolutionembedded in another

process

Handle Resolutionembedded in another

process


• Ownership is at the handle level

• Administrators defined by handles

• Administrator handles contain keys

• All admin transactions validated via challenge/response from server to client

• Allows distributed administration

HS Administration


Metadata Collection and DOI Registration

Electronic version ofAdvanced Synthesis & Catalysispublished by Wiley Interscience

Handle Data and Metadata

<doi> 10.XXXX/1234</doi><url>http://www3.interscience.wiley.com/…</url>b/<jname>Advanced Synthesis & Catalysis</jname><title>New Horizona</title><author>Bill Smith</author><page>786-980</page><abstract>Lorem ipsum dolor sit amet, consectetuer elit, sed diem nonummy nibh euismod. Lorem ipsumdolor sit amet, consectetuer adipiscing elit, sed diem nonummy nibh euismod</abstract>

http://www3.interscience.wiley.com/...


Handle data and metadata

Collection Service

Handle System

WholesaleMetadataCollection

Handle dataMetadata

Other Data Services VARs

• Indexes• Filters• Queries


Handle data and metadata

Collection Service

Handle System

WholesaleMetadataCollection

Handle dataMetadata

Other Data Services VARs

• Indexes• Filters• Queries

Publisher 1

Publisher 3

Publisher 2

Publisher n

Appropriate Copy Problem

http://abc.com/article.html http://abc.com/article.html

10.123/456

Handle System

ABC Journalpublisherabc.com

Reference withDOI for

article.htmlin ABC Journal

XYZ University

Local Copy ofarticle.html

in ABC Journal

http://dx.doi.org/10.123/456

dx.doi.orgproxy server

article.html

Appropriate Copy Problem: solved

Handle System




XYZ University


in ABC Journal

http://dx.doi.org/10.123/456?cookie


understands cookies

Local Server

Redirect to Local Server

MetadataDatabase

Metadata?

Metadata

Appropriate Copy Problemsolved w/o local copy

Handle System




XYZ University


in ABC Journal

Local Server

MetadataDatabaseX

article.html

Metadata?

Metadata


understands cookies

Appropriate Copy Problemextensible solution

Handle System




XYZ University


in ABC Journal

Local Server

Meta1.com

http://dx.doi.org/10.123/456?cookie

Redirect to Local Server

Meta2.com

Meta3.comMetadata Collection Services

Xarticle.html


understands cookies

Metadata Location?

Meta1.com

Metadata?

Metadata

Repository Overview

Digital Libraries Without a Digital Object System

Web Server

Other DigitalLibrary Servers

or Services

Web-basedDigital Library

Client

HTTP

HTTPContent Operations

(CGI scripts)

CGI sCGI s ContentData

ContentData

Web Page

Web Page

Web Server

Digital Libraries With a Digital Object System

DIGITAL

OBJECT

SYSTEM

Content Operations(scripts, servlets, other

operations)

ContentData

ContentData

HTTP

Other DigitalLibrary Servers

or Services

Web-basedDigital Library

Client

Dissemination

RAP

Request

RAP

Request

Web Page

Dissemination


• Exists within the Digital Object Architecture with the goal of making information a first class citizen on the Internet.

• Allows high level information to be moved around on the Internet much as packets of data are today.

•Aggregates relevant heterogeneous data and metadata.

• Solves the who is where problem of network addressing by using the CNRI Handle System®, a location independent global naming service.

• Describes the what of information in an concise and extensible manner.

Digital Information Object


Digital Information Object Intents of Use

• The Intents of use extensible typing mechanism specifies what a Digital Information Object contains.

• A specific Digital Information Object’s intent of use is described as a content type.

• Content types are registered and uniquely identifiable.

• A content type defines a unique set of operations that can be performed on specific information type.

• The set of operations is known as a content type signature.

• A content type signature can be implemented in different ways in the form of mobile code called servlets.

Complex Digital Object Dissemination

Laptop with modem

.jpg

.ra

PC with T1 Connection.exe

.qt

Digital Phone .xml

PDA with wirelessconnection

.jpg

.pdf

Digital ObjectDigital ObjectContent Type(s)Content Type(s) RequestsRequests

InformationInformation

Digital Object Overview

DisseminationsDisseminations

Unique IdentifierUnique Identifier

HamletHamlet

It’s a BookIt’s a Book Get Page(2)Get Page(2)


HamletHamlet

Hamlet

•Digital objects are uniquely identified in a given name space.

•Data elements reference sequences of typed bytes.

•A Digital Object can have zero or more Content Types to reflect the intents of use of its creator.

DataElement

DataElement

DataElement

DataElement

HamletContent Type

Operations

Content TypeOperations


Repository

Digital Object Repository

RA

P

ClientClient

•Provides distributed Digital Object storage.

•Behaves as a Digital Object.

•Provides a dynamic acquisition and execution mechanism for the mobile code that implements the content type operations.

•Exclusively accessed using the Repository Access Protocol (RAP).

DisseminateDeposit

1 to many

Type Signature

Servlet

TypeSignature

Implementation

TypeSignature

Implementation

Type Signature API

ServletImplementation

ServletImplementation

Servlet API

Ser

vice

s A

PI

Ref

eren

ces

Content TypeOperations

Content Type Extensibility

hdl:type/repositoryhdl:type/repository

hdl: type/repositoryhdl: type/typedef URN

Handle Service

hdl:type/repository IOR:DLShttp://www.type.orgURL

hdl: type/book hdl: type/typedefURN

hdl: type/book1 hdl: type/typeimpl URN

hdl:type/typeimpl hdl:type/repositoryURN

Registerhdl:type/typedefhdl:type/typedef

hdl:type/book

Type Signature

hdl:type/book

Type Signature

hdl:type/typeimplhdl:type/typeimpl

hdl:type/book1

Servlet

hdl:type/book1

Servlet

Content Type Registration

Identifier

IdentifierIdentifier

Type SignatureType Signature

ServletServlet AttachmentsAttachments

Disseminator

Digital Object Structures

DisseminatorIdentifierIdentifier



Identifier

DataElement

DataElement

DataElement

DataElement

Type Registry

Handle ServiceHandle Servicehdl:type/repositoryhdl:type/repository

signature

servlet

100.1/PH150

MetadataMetadata

100.1/Metadata100.1/Metadata

Disseminator

hdl:type/repositoryhdl:type/repository

Digital Object Structures

DisseminatorImageImage

Identifier

.jpg.jpg.gif.gif

Type Registry

Handle ServiceHandle Service

.txt.txt

AttachmentAttachment

100.1/MetadataImplementation

AttachmentsAttachments

100.1/ImageImplementation100.1/ImageImplementation

100.1/Image100.1/Image

signature

servlet

RepositoryRepository

Deposit

IdentifierClient C

Client C

Disseminator

Servlet

XYZ-1

Servlet

XYZ-1

Content Type Extensibility Mechanism


Type Signature XYZType Signature XYZ

AttachmentAttachment

Repository 2Repository 2

Deposit

DepositData

ElementData

ElementData

ElementData

Element

Client A

Client A

XYZ

Client B

Client B

XYZ-1

Dynamic Acquisition of Mobile code

Disseminate

Client D

Client D

Secure Digital Object Environment

Extensible Services

Extensible Dissemination Mechanism


DisseminatorIdentifierIdentifier


TypeSignature

TypeSignature

Signature API Servlet API

Ser

vice

s A

PI

ServletServlet

Attachments

Disseminations

Req

ues

ts

Resu

lts

RepositoryServices

RepositoryServices


DataElement

DataElement

Disseminations

Req

ues

ts

Resu

lts


Digital Object Chaining

• Provides a building block approach to information management.

•Enables the creation of information and operation links.

•Content Chaining: a digital object’s data element can reference its respective content.

•Operations Chaining: servlets can dynamically establish links to external resources or digital object when executed.

•Content Type Chaining: chaining servlets can be designed to dynamically build digital object chains from input parameters.

Content Chaining Mechanism

StaticServiceRequest

StaticServiceRequest

Digital Object

•Digital Object ID•Disseminator ID

•Method Request•Parameters



orData

ElementData

Element

Typed BytesTyped Bytes

Type Signature

Type Signature ServletServlet

Extensible Services

•Type Signature ID•Servlet ID




Operation Chaining Mechanism

or•Digital Object ID

•Disseminator ID•Method Request

•Parameters


•Method Request•Parameters Digital Object

DynamicServiceRequest

DynamicServiceRequest

Method RequestS

ervi

ces

AP

I

Servlet API

ServletServlet





Type Signature

Type Signature ServletServlet

Extensible Services

Digital Object

self

Digital Object Chaining Example

Example: ask the Babel Fish Object: generate an audio version of a French translation of Shakespeare's Hamlet.

Babel FishBabel Fish

Babel FishType

44 55

Babel TranslatorBabel Translator

66

11

ShakespeareShakespeare

33

88

Audio Tools

77

22

HamletHamlet

Data Exchange By Chaining

Query SystemQuery System

•Digital Object chaining allows for homogeneous data exchanges in a heterogeneous data environment.

•Digital Object Chaining provide a layer of abstraction over data formats, encoding and transport protocols.

Type A

Type B

ServicesServices

Type A

Type A

Type A

Date post:	27-Mar-2015
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Handle System Overview Larry Lannom Corporation for National Research Initiatives

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