Transcript Web 2.0 in a Web Services and Grid Context Part I: CTS2007 Web 2.0 Tutorial CTS 2007 Embassy Suites Hotel-Lake Buena Vista Resort, Orlando,

Web 2.0 in a Web Services and
Grid Context
Part I: CTS2007 Web 2.0 Tutorial
CTS 2007
Embassy Suites Hotel-Lake Buena Vista Resort, Orlando, FL, USA
May 25 2007
Geoffrey Fox and Marlon Pierce
Computer Science, Informatics, Physics
Pervasive Technology Laboratories
Indiana University Bloomington IN 47401
[email protected]
http://www.infomall.org
1
Applications, Infrastructure,
Technologies




This field is confused by inconsistent use of terminology
– this is what I mean
Web Services, Grids and Web 2.0 (Enterprise 2.0) are
technologies
These technologies combine and compete to build
electronic infrastructures termed e-infrastructure or
Cyberinfrastructure
e-moreorlessanything is an emerging application area
of broad importance that is hosted on the
infrastructures e-infrastructure or Cyberinfrastructure
e-moreorlessanything is the Application







‘e-Science is about global collaboration in key areas of science,
and the next generation of infrastructure that will enable it.’ from
its inventor John Taylor Director General of Research Councils
UK, Office of Science and Technology
Similarly e-Business captures an emerging view of corporations as
dynamic virtual organizations linking employees, customers and
stakeholders across the world.
Net Centric computing is a similar DoD vision
This generalizes to e-moreorlessanything
A deluge of data of unprecedented and inevitable size must be
managed and understood.
People (see Web 2.0), computers, data and instruments must be
linked.
On demand assignment of experts, computers, networks and
storage resources must be supported
3
Role of Electronic infrastructure

Supports integration of data, people, computers for
• Distributed Science or e-Science (US, Cyberinfrastructure)
• Command and Control (US, Global Information Grid)
• e-Business e-Science etc. (Europe, e-Infrastructure)





Exploits Internet technology (Web2.0) adding (via Grid
technology) management, security, supercomputers etc.
It has two aspects: parallel – low latency (microseconds)
between nodes and distributed – highish latency (milliseconds)
between nodes
Parallel needed to get high performance on individual 3D
simulations, data analysis etc.
Distributed aspect integrates already distinct components
Electronic infrastructure is in general a distributed collection
of parallel systems and presented as services (often Web
services) that are “just” programs or data sources packaged
for distributed access
4
Not so controversial Ideas


Distributed software systems are being “revolutionized” by
developments from e-commerce, e-Science and the consumer
Internet. There is rapid progress in technology families termed
“Web services”, “Grids” and “Web 2.0”
The emerging distributed system picture is of distributed services
with advertised interfaces but opaque implementations
communicating by streams of messages over a variety of protocols
• Complete systems are built by combining either services or predefined/preexisting collections of services together to achieve new capabilities


Currently Grids are built using Web Services with possible
enhancements like WSRF which we call Narrow or Web service
Grids
We expect that future systems will be built as Broad Grids which
are a collection of services mixing Web Service and Web 2.0
architectures

Web
2.0
and
Web
Services
I
Web Services have clearly defined protocols (SOAP) and a well
defined mechanism (WSDL) to define service interfaces
• There is good .NET and Java support
• The so-called WS-* specifications provide a rich sophisticated but
complicated standard set of capabilities for security, fault tolerance, metadata, discovery, notification etc.


“Narrow Grids” build on Web Services and provide a robust
managed environment with growing adoption in Enterprise
systems and distributed science (so called e-Science)
Web 2.0 supports a similar architecture to Web services but has
developed in a more chaotic but remarkably successful fashion
with a service architecture with a variety of protocols including
those of Web and Grid services
• Over 400 Interfaces defined at http://www.programmableweb.com/apis


Web 2.0 also has many well known capabilities with Google
Maps and Amazon Compute/Storage services of clear general
relevance
There are also Web 2.0 services supporting novel collaboration
modes and user interaction with the web as seen in social
networking sites, portals, MySpace, YouTube,
Web 2.0 and Web Services II




I once thought Web Services were inevitable but this is
no longer clear to me
Web services are complicated, slow and non functional
• WS-Security is unnecessarily slow and pedantic
(canonicalization of XML)
• WS-RM (Reliable Messaging) seems to have poor
adoption and doesn’t work well in collaboration
• WSDM (distributed management) specifies too much
There are de facto standards like Google Maps and
powerful suppliers like Google which “define the rules”
One can easily combine SOAP (Web Service) based
services/systems with HTTP messages but the “lowest
common denominator” suggests additional
structure/complexity of SOAP will not easily survive
Old and New (Web 2.0) Community Tools




e-mail and list-serves are oldest and best used
Kazaa, Instant Messengers, Skype, Napster, BitTorrent for P2P
Collaboration – text, audio-video conferencing, files
del.icio.us, Connotea, Citeulike, Bibsonomy, Biolicious manage
shared bookmarks
MySpace, YouTube, Bebo, Hotornot, Facebook, or similar sites
allow you to create (upload) community resources and share
them; Friendster, LinkedIn create networks
• http://en.wikipedia.org/wiki/List_of_social_networking_websites



Writely, Wikis and Blogs are powerful specialized shared
document systems
ConferenceXP and WebEx share general applications
Google Scholar tells you who has cited your papers while
publisher sites tell you about co-authors
• Windows Live Academic Search has similar goals

Note sharing resources creates (implicit) communities
• Social network tools study graphs to both define communities
and extract their properties
“Best Web 2.0 Sites” -- 2006

Extracted from http://web2.wsj2.com/
Social Networking

Start Pages

Social Bookmarking

Peer Production News

Social Media Sharing

Online Storage
(Computing)

9
Web 2.0 Systems are Portals, Services, Resources

Captures the incredible development of interactive Web
sites enabling people to create and collaborate
Mashups v Workflow?





Mashup Tools are reviewed at http://blogs.zdnet.com/Hinchcliffe/?p=63
Workflow Tools are reviewed by Gannon and Fox
http://grids.ucs.indiana.edu/ptliupages/publications/Workflow-overview.pdf
Both include
scripting in PHP,
Python, sh etc. as
both implement
distributed
programming at level
of services
Mashups use all
types of service
interfaces and do not
have the potential
robustness (security)
of Grid service
approach
Typically “pure”
HTTP (REST)
11
Grid Workflow Datamining in Earth Science

NASA GPS

Work with Scripps Institute
Grid services controlled by workflow process real time
data from ~70 GPS Sensors in Southern California
Earthquake
Streaming Data
Support
Archival
Transformations
Data Checking
Hidden Markov
Datamining (JPL)
Real Time
Display (GIS)
12
Web 2.0 uses all types of Services

Here a Gadget Mashup uses a 3 service workflow with
a JavaScript Gadget Client
13
Web 2.0 APIs


http://www.programmable
web.com/apis has (May 14
2007) 431 Web 2.0 APIs
with GoogleMaps the most
often used in Mashups
This site acts as a “UDDI”
for Web 2.0
The List of
Web 2.0 API’s





Each site has API and
its features
Divided into broad
categories
Only a few used a lot
(42 API’s used in
more than 10
mashups)
RSS feed of new APIs
Amazon S3 growing
in popularity
APIs/Mashups per Protocol
Distribution
Number of
APIs
google
maps
Number of
Mashups
del.icio.us
virtual
earth
411sync
yahoo! search
yahoo! geocoding
technorati
netvibes
yahoo! images
trynt
yahoo! local
amazon
ECS
google
search
flickr
SOAP
ebay
youtube
amazon S3
REST
live.com
XML-RPC
REST,
REST,
REST,
JS
Other
4 more Mashups
each day



Growing number of commercial Mashup Tools
For a total of 1906
April 17 2007 (4.0 a
day over last
month)
Note ClearForest
runs Semantic Web
Services Mashup
competitions (not
workflow
competitions)
Some Mashup
types: aggregators,
search aggregators,
visualizers, mobile,
maps, games
Mash
Planet
Web 2.0
Architecture
http://www.imagine
-it.org/mashplanet
Display too large to
be a Gadget
18
Searched on Transit/Transportation
19
Google Maps Server
Marion County
Map Server
(ESRI ArcIMS)
Must provide adapters
for each Map Server
type .
Tile Server requests
map tiles at all zoom
levels with all layers.
These are converted
to uniform projection,
indexed, and stored.
Overlapping images
are combined.
A “Grid” Workflow
(built in Java!)
Hamilton County
Map Server
(AutoDesk)
Adapter
Adapter
Adapter
Tile Server
Cache Server
Browser +
Google Map API
Cass County Map
Server
(OGC Web Map
Server)
Browser client fetches
image tiles for the
bounding box using
Google Map API.
The cache server
fulfills Google map
calls with cached tiles
at the requested
bounding box that fill
the bounding box.
Uses Google Maps clients and
server and non Google map APIs
20
Indiana Map Grid Workflow/Mashup
GIS Grid of “Indiana Map” and ~10 Indiana counties with accessible Map (Feature)
Servers from different vendors. Grids federate different data repositories (cf Astronomy
VO federating different observatory collections)
21
Grid-style portal as used in Earthquake Grid
The Portal is built from portlets
– providing user interface
fragments for each service
that are composed into the
full interface – uses OGCE
technology as does planetary
science VLAB portal with
University of Minnesota
Now to Portals
22
Note the many competitions powering Web 2.0
Mashup Development
Portlets v. Google Gadgets





Portals for Grid Systems are built using portlets with
software like GridSphere integrating these on the
server-side into a single web-page
Google (at least) offers the Google sidebar and Google
home page which support Web 2.0 services and do not
use a server side aggregator
Google is more user friendly!
The many Web 2.0 competitions is an interesting model
for promoting development in the world-wide
distributed collection of Web 2.0 developers
I guess Web 2.0 model will win!
23
Typical Google Gadget Structure
Google Gadgets are an example of
Start Page technology
See http://blogs.zdnet.com/Hinchcliffe/?p=8

… Lots of HTML and JavaScript </Content> </Module>
Portlets build User Interfaces by combining fragments in a standalone Java Server
Google Gadgets build User Interfaces by combining fragments with JavaScript on the client
Web 2.0 v Narrow Grid I





Web 2.0 and Grids are addressing a similar application class
although Web 2.0 has focused on user interactions
• So technology has similar requirements
Web 2.0 chooses simplicity (REST rather than SOAP) to lower
barrier to everyone participating
Web 2.0 and Parallel Computing tend to use traditional (possibly
visual) (scripting) languages for equivalent of workflow whereas
Grids use visual interface backend recorded in BPEL
Web 2.0 and Grids both use SOA Service Oriented Architectures
“System of Systems”: Grids and Web 2.0 are likely to build
systems hierarchically out of smaller systems
• We need to support Grids of Grids, Webs of Grids, Grids of
Services etc. i.e. systems of systems of all sorts
25
Web 2.0 v Narrow Grid II

Web 2.0 has a set of major services like GoogleMaps or Flickr
but the world is composing Mashups that make new composite
services
• End-point standards are set by end-point owners
• Many different protocols covering a variety of de-facto standards





Narrow Grids have a set of major software systems like Condor
and Globus and a different world is extending with custom
services and linking with workflow
Popular Web 2.0 technologies are PHP, JavaScript, JSON,
AJAX and REST with “Start Page” e.g. (Google Gadgets)
interfaces
Popular Narrow Grid technologies are Apache Axis, BPEL
WSDL and SOAP with portlet interfaces
Robustness of Grids demanded by the Enterprise?
Not so clear that Web 2.0 won’t eventually dominate other
application areas and with Enterprise 2.0 it’s invading Grids
The world does itself in large numbers!
Web 2.0 v Narrow Grid III




Narrow Grids have a strong emphasis on standards and
structure; Web 2.0 lets a 1000 flowers (protocols) and a million
developers bloom and focuses on functionality, broad usability
and simplicity
• Semantic Web/Grid has structure to allow reasoning
• Annotation in sites like del.icio.us and uploading to
MySpace/YouTube is unstructured and free text search
replaces structured ontologies
Portals are likely to feature both Web and “desktop client” technology
although it is possible that Web approach will be adopted more or less
uniformly
Web 2.0 has a very active portal activity which has similar architecture to
Grids
• A page has multiple user interface fragments
Web 2.0 user interface integration is typically Client side using Gadgets AJAX
and JavaScript while
• Grids are in a special JSR168 portal server side using Portlets WSRP and
Java
27
The Ten areas covered by the 60 core WS-*
Specifications
WS-* Specification Area
Typical Grid/Web Service Examples
1: Core Service Model
XML, WSDL, SOAP
2: Service Internet
WS-Addressing, WS-MessageDelivery; Reliable
Messaging WSRM; Efficient Messaging MOTM
3: Notification
WS-Notification, WS-Eventing (PublishSubscribe)
4: Workflow and Transactions
BPEL, WS-Choreography, WS-Coordination
5: Security
WS-Security, WS-Trust, WS-Federation, SAML,
WS-SecureConversation
6: Service Discovery
UDDI, WS-Discovery
7: System Metadata and State
WSRF, WS-MetadataExchange, WS-Context
8: Management
WSDM, WS-Management, WS-Transfer
9: Policy and Agreements
WS-Policy, WS-Agreement
10: Portals and User Interfaces
WSRP (Remote Portlets)
WS-* Areas and Web 2.0
WS-* Specification Area
Web 2.0 Approach
1: Core Service Model
XML becomes optional but still useful
SOAP becomes JSON RSS ATOM
WSDL becomes REST with API as GET PUT etc.
Axis becomes XmlHttpRequest
2: Service Internet
No special QoS. Use JMS or equivalent?
3: Notification
Hard with HTTP without polling– JMS perhaps?
4: Workflow and Transactions
(no Transactions in Web 2.0)
Mashups, Google MapReduce
Scripting with PHP JavaScript ….
5: Security
SSL, HTTP Authentication/Authorization,
OpenID is Web 2.0 Single Sign on
6: Service Discovery
http://www.programmableweb.com
7: System Metadata and State
Processed by application – no system state –
Microformats are a universal metadata approach
8: Management==Interaction
WS-Transfer style Protocols GET PUT etc.
9: Policy and Agreements
Service dependent. Processed by application
10: Portals and User Interfaces Start Pages, AJAX and Widgets(Netvibes) Gadgets
Drivers for Future





Web 2.0 has momentum as it is driven by success of
social web sites and the user friendly protocols
attracting many developers of mashups
Grids momentum driven by the success of eScience and
the commercial web service thrusts largely aimed at
Enterprise
We expect applications such as business and DoD
where predictability and robustness important to be
built on a Web Service (Narrow Grid) core with Web
2.0 functionality enhancements
Simplicity, supporting many developers are forces
pressuring Grids!
Robustness and coping with unstructured blooming of
a 1000 flowers are forces pressuring Web 2.0