Wednesday, August 29, 2012

A Scalable Multi-tenant Architecture for Business Process Executions

The journal paper “A Scalable Multi-tenant Architecture for Business Process Executions” is our latest publication which discusses in detail our work on extending scalability and multi-tenancy support to Business Processes. It was recently published in International Journal of Web Services Research (IJWSR), vol. 9(2), pp. 21-41, April-June 2012. Authors of this paper are Milinda Pathirage, Dr. Srinath Perera, Indika KumaraDenis Weerasiri and Dr. Sanjiva Weerawarana.

Abstract of the paper is
Cloud computing, as a concept, promises cost savings to end-users by letting them outsource their non-critical business functions to a third-party in pay-as-you-go style. However, to enable economic pay-as-you-go services, the end-users need Cloud middleware that maximizes sharing and support near-zero cost for unused applications. Multi-tenancy, which let multiple tenants to share a single application instance securely, is a key enabler for building such a middleware. On the other hand, Business processes capture Business logic of organizations in an abstract and reusable manner, and hence play a key role in most organizations. This paper presents the design and architecture of a scalable Multi-tenant Workflow engine while discussing in detail the potential use cases of such architecture. Primary contributions of this paper are motivating workflow multi-tenancy, and the design and implementation of a scalable multi-tenant workflow engine that enables multiple tenants to run their workflows securely within the same workflow engine instance without modifications to the workflows. Furthermore, the workflow engine supports process sharing and process variability across the tenants and discusses its ramifications.

Paper can be accessed from here.

Monday, August 27, 2012

A journey through the history of computers

Computer History Museum, a place I like a lot in Mountain view, California. It’s the world’s largest history museum which explores the computing revolution and its impact on our lives. The journey starts from earliest calculating devices like "Abacus" to every landmark in the modern digital era.

Some of the pictures from the visit.

At the entrance
Who invented the computer?
The evolution of programming languages
An early IBM server
An early Google server
Some thoughts about .com boom and bust
On the way to the museum 

Saturday, August 25, 2012

WSO2 BPS v3.0.0 Beta is out

WSO2 BPS v3.0.0 Beta is out The release candidate of WSO2 BPS v.3.0.0 was released with lot of long awaited features and with a load of bug fixes.

Some of the new features in the Beta release are
  • WS- Human Task support 
  • WS- BPEL4People support 
  • BPEL Instance Illustrator 
  • BPEL deployment descriptor editor 
  • Improved BPS management console and BPS documentation 

You can download the binary distribution from here.

Monday, August 20, 2012

1st Google+ Hangout

This is cool and runs smooth with an average 3G cellular connection.

Thursday, August 16, 2012

Configuring a log4j logger to WSO2 ESB main sequence

Configuring separate loggers to different proxy services is a useful feature in WSO2 ESB.
You can do this by setting a log appender as follows.

Here “__SynapseService” is the SERVICE_LOGGER for the main sequence. Similarly you can use the name of your proxy service as the SERVICE_LOGGER to manage logs separately for each of those proxies.