16.6.07

Anatomy of the Linux kernel - History and architectural decomposition

Anatomy of the Linux kernel
The Linux® kernel is the core of a large and complex operating system, and while it's huge, it is well organized in terms of subsystems and layers. In this article, you explore the general structure of the Linux kernel and get to know its major subsystems and core interfaces. Where possible, you get links to other IBM articles to help you dig deeper.

Given that the goal of this article is to introduce you to the Linux kernel and explore its architecture and major components, let's start with a short tour of Linux kernel history, then look at the Linux kernel architecture from 30,000 feet, and, finally, examine its major subsystems. The Linux kernel is over six million lines of code, so this introduction is not exhaustive. Use the pointers to more content to dig in further.

5.4.07

SCA: 1.0 and OASIS - Bobby Woolf's dW Blog

From Bobby Woolf: WebSphere SOA and J2EE in Practice

Monday April 02, 2007

Service component architecture (SCA) has reached some important milestones.

In "SCA V1.0 Publication & OASIS Standardization Intent Announcement," the OSOA announces SCA v1.0, to go with SDO 2.1. The specs have now been submitted to OASIS for ratification as a standard.

I've talked about Service Component Architecture (SCA), the new programming model designed specifically for SOA, and Service Data Objects (SDO), a programming model for portable data. SCA is built into WebSphere Process Server and is being standardized by the Open Service Oriented Architecture (OSOA) organization, a collaboration of a dozen top software vendors including IBM.

You can get more links on my wiki; Open Service-Oriented Architecture is a good place to start.

3.2.07

Oracle Service Registry 10.1.3.1 now available

Oracle SOA Suite 10g Release 3 (10.1.3.1.0) Downloads: "Oracle Service Registry 10g Runs on all certified platforms (80 MB)"

The Oracle Service Registry 10.1.3.1 has been released and is available for download from OTN. This version of Registry is fully compatible with the 10.1.3.1 (SOA) releases of Oracle Application Server and OC4J standalone.

The product installer, a ReadMe document and the product documentation can be downloaded from the SOA/Web Center download page on OTN

Note that the installer can be used with all supported versions of Windows, Linux and Unix. This is a change from the 10.1.3 release, which had different Windows/Linux and Unix installers.

** WHAT'S NEW IN ORACLE SERVICE REGISTRY 10.1.3.1 **

Key enhancements other than infrastructure changes include:

* Support for the Oracle XML-based lightweight security provider

* Use of Oracle data sources, meaning that RAC support is now provided out-of-the-box

* Support for the following non-Oracle databases:
** Microsoft SQL Server 2005
** IBM DB2 8.0 +
** Sybase ASE 12.5 +

* An embedded Oracle Lite database. This configuration is supported on Windows only and is suitable for demonstration purposes only.


** SUPPORTED ORACLE APPLICATION SERVER VERSIONS **

Oracle Service Registry 10.1.3.1 is supported on the following Oracle versions:

Oracle Application Server 10g R3 (10.1.3.1)
OC4J Standalone 10g R3 (10.1.3.1)
Oracle Application Server 10g R2 (10.1.2.0.2)
OC4J 10g R2 (10.1.2.0.2)

Note that because the new release uses the Oracle JSP (OJSP) engine instead of Apache Jasper, an OJSP patch is required if running on Oracle Application Server/OC4J R2 (10.1.2.0.2). The patch can be downloaded from Metalink:

Patch: 4936151
Release: 10.1.2.0.2
Platform: Generic

30.1.07

Help wanted: qualified SOA architects

Help wanted: qualified SOA architects: "Help wanted: qualified SOA architects
By Rich Seeley, News Writer
29 Jan 2007 | SearchWebServices.com

The Association of Open Group Enterprise Architects (AOGEA) was founded today in an attempt to fill a competence gap in the face of analyst and vendor fears that unqualified architects might slow or even doom SOA adoption."

24.1.07

Study Finds Open Source Benefits Business

Study Finds Open Source Benefits Business
'Free' software makes economic sense.
Floss for economic health. That's the conclusion of a newly released European Commission studyOpen Source Software (Floss) on the European IT sector. on the impact of Free, Libre, and

The EC study, conducted by UNU-Merit, a research institute of the University of Maastricht in the Netherlands, finds that the use of open source software adds 263 billion Euros to the European economy and "the number of employees among firms contributing code to Floss projects is at least 570,000."

It also says that open source software programmers, nearly half of which are based in Europe, volunteer least 800 million Euros (roughly $1 billion U.S.) worth of labor.

The report calls for "correcting current policies and practices that implicitly or explicitly favor proprietary software" by offering fairer R&D incentives, supporting standardization, avoiding vendor lock-in in education settings, equitable tax treatment for open source contributors, and encouraging partnerships between businesses and the open source community.

The report estimates that the Floss-related share of the economy could reach 4% of European GDP by 2010.

"By providing a skills development environment valued by employers and retaining a greater share of value addition locally, Floss can encourage the creation of [businesses] and jobs," the report says.

That's a perspective shared by Richard Gorman, a venture partner at Silicon Valley VC firm Bay Partners, which invests in open source companies. "Open source is clearly a major trend and is clearly an economic stimulus for the economy today," he said. "The reason we like the open source business model is that it's a way of entering markets and solving customer problems in a very effective way, both from a control and an economic perspective."

Some of the report's findings and recommendations may rankle leading proprietary software makers such as Apple and Microsoft.

One policy recommendation seems particularly applicable to Apple and the ties between the iPod and iTunes Music Store: "Explore how unbundling between hardware and software can lead to a more competitive market and ease forms of innovation that are not favored by vertical integration."

And one of the report's findings is that users of Microsoft Office are no more productive than users of OpenOffice. "We also investigated the productivity of the employees in using Microsoft Office and OpenOffice.org," the report says. "Office suites are widely used and are a good test bed and representative for a comparison on issues like effort and time spent in the daily routine of work. Delays in the task deliveries may have a bigger impact than costs on the organization's management. Our findings report no particular delays or lost of time in the daily work due to the use of OpenOffice.org."

The report, however, stops short of recommending businesses switch to free applications such as OpenOffice because "employees may perceive that their work is under-valued using 'cheap' OSS products." It says organizations should consider that migrating away from proprietary software might have implications beyond cost.

Microsoft maintains that the total cost of ownership for Windows software is less than Linux and continues to host dozens of case studies, white papers, and customer testimonials to that effect on its Get the Facts Web site.

But Gorman insists the open source software makes economic sense. "It's a very good business model for entering large, existing markets and taking significant share, and creating significant customer and investor value," he said. "If you're an incumbent competing with a new company that's an open source company, it's very difficult to adjust or change your business model to be competitive. Usually by the time they end up adjusting, it's too late."