The Open Services Gateway Initiative (OSGi) Alliance is working to realize
the vision of a "universal middleware" that will address issues such as
application packaging, versioning, deployment, publication, and discovery.
In this article we'll examine the need for the kind of container model
provided by the OSGi, outline the capabilities it would provide, and discuss
its relationship to complementary technologies such as SOA, SCA, and Spring.
Enterprise software is often composed of large amounts of complex
interdependent logic that makes it hard to adapt readily to changes in
requirements from the business. You can enable this kind of agility by
following a Service Oriented Architecture (SOA) pattern that refactors a
system into application modules grouped by business functions that expose
their public functionality as services (interfaces).
For example, a customer... (more)
Benchmarking any distributed computing middleware product is a complex task.
Knowing how well a distributed infrastructure will perform under heavy load
with a large number of concurrently connected users is a key factor in
planning a development and deployment strategy.
With the advent of Java Message Service (JMS) as the standard for a global
class middleware infrastructure, development organizations can enjoy the
luxury of building distributed applications using a common set of APIs and
message delivery semantics. At the same time they can pick and choose from a
variety of JM... (more)
In a recent "Strategic Planning" research note, Gartner issued a prediction
that "by 2004, more than 25 percent of all standard Web services traffic will
be asynchronous...." and "by 2006, more than 40 percent of the standard Web
services traffic will be asynchronous."
One of the cornerstones of Web services interoperability is the SOAP (Simple
Object Access Protocol). SOAP began simply as a way of performing a
synchronous RPC (Remote Procedure Call) across the Internet over an HTTP
However, the current "owners" of SOAP the XML Protocol WG at the W3C
have been t... (more)
Message-centric vs RPC-style Web services is a long-standing debate and bone
of contention regarding the proper use of Web services technologies. Early
renditions of SOAP and XML-RPC were all about providing RPC-style
interactions...in fact, that's all that was supported, so there really wasn't
much choice in the matter.
RPC-style interfaces have their advantages: immediate gratification of
request/response, and a programming model whereby remote procedures are
exposed in a way that mimics the underlying object architecture of the
applications concerned, allowing a developer to ... (more)
Open standards for reliable Web services messaging, such as WS-Reliability,
can provide the missing link to bridge the gap between organizations and help
make Web services a truly enterprise-capable technology for standards-based
systems integration, says Web Services Journal technical editor David
Along with security, reliable asynchronous communications has been one of the
gaping holes in today's Web services architecture. Lack of reliability, due
to the inherent nature of using SOAP over protocols such as HTTP, is one of
the biggest obstacles to the adoption of Web s... (more)