Systems and Applications Management
Let's talk QoS
Sometimes it is necessary to interject a dose of IT operations reality into the excitement surrounding new technologies and application development paradigms like Web services. It's a thankless job but someone has to do it because if the business is going to bet it's future on new technologies then someone has to think through how to excel at delivering it in a production environment.
Let's start by saying that Web services looks like a technology that adds real value to the enterprise. The promise of Web services is that software functionality can be more readily aggregated or replaced as the business requires making for a much more dynamic infrastructure that can rapidly adjust to changing business needs. If one Web services provider is not living up to the business' needs, then they can be readily replaced and survival-of-the-fittest will drive the pretenders out of the market.
This is good, but what it means in the production environment is that Web services will create complex software ecologies. Ecologies -- not architectures -- because ecologies are dynamic entities made up of changeable components and non-intuitive interdependences that determine whether a healthy balance is achievable. As complexity and dynamism grow, end-to-end performance issues must be addressed earlier in the traditional application life cycle. With the software ecologies, performance becomes a critical issue during creation. In other words, quality of service metrics are critical criteria when considering using a particular Web service, therefore they should be built into Web services from the start.
It is obvious that Web services providers should be chosen on the basis of their ability to deliver services of superior quality. Some quality of service (QoS) categories to rate providers would be availability, accessibility, integrity, performance, and reliability. However, there appears to be little in the current Web services protocols for monitoring QoS metrics and using them to make decisions. In addition, the current expectation is for enterprises to develop the capabilities needed to evaluate QoS metrics to qualify or replace providers themselves. Concern over the lack of performance-related capabilities shows up in our Web services survey, however, our survey also shows that this concern is not slowing implementation.
THE HURWITZ TAKE: IT organizations are having a hard enough time managing to SLAs based on existing multi-tiered software architectures that are for the most part stable. The existing management standards and installed management tools are not up to dealing with software ecologies that will evolve as more Web services are implemented and companies use external providers to build complex business services. Hurwitz Group estimates that these complex software ecologies will reach a critical mass in two to three years. This gives the standards bodies and third-party management vendors some breathing room. The key to remember, however, is that QoS can no longer be delivered as an afterthought in a Web services world.
Copyright 2002 Hurwitz Group Inc. This article is excerpted from TrendWatch, a weekly publication of Hurwitz Group Inc. - an analyst, research, and consulting firm. To register for a free email subscription, click here.
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