Web Services Management: A Standards-Based Common Architecture Part 2, Page 2
The Complete Picture
To put the above architecture proposal in perspective, it is imperative to discuss how the current Web services and IT management scenario can evolve to this model of management. Let us look at what else needs to happen apart from implementing and installing management infrastructure based on the architecture proposed in this paper.
First, let us understand that a Web services management infrastructure is targeted at administrators in an IT organization. However, current IT administrators are trained more for hardware, storage, and network infrastructure management rather than software "application" management, which is what Web services management would involve. Some degree of re-orientation of the administrators might be needed. An additional complexity arises from the fact that some of the service-level parameters in Web services are much closer to business functions, and hence should be determined by people in business decision roles.
Secondly, Web services QoS, occasionally, would involve services outside a management domain (for example, in a composed service scenario). Software and hardware intermediaries for service provisioning also affect the service levels if end-to-end SLA guarantees are made. Having common schemas for management data accessible via standard protocols would help in integrating the management information across domains. But, guarantees across domains would have to be made more carefully.
Lastly, following are some more challenges to consider with respect to Web services management:
- Accessing Web services management data over the Internet will require a robust and end-to-end security environment during operation. Security standards and implementations for Web services are still evolving and will require industry-wide agreement before widespread adoption.
- Understanding the value in adopting common management standards by Web services platform vendors is needed. Companies will have to agree and adopt common standards which could potentially commoditize the platforms.
Let us briefly look at some of the related products that exist today. Current products available in the market are rudimentary from a management perspective and follow varied approaches to Web services management. They have different notions of what Web services management means and their implementations are very different and mostly proprietary. Also, the products themselves are evolving by providing more functionalities and better integration with Web services platforms. However, there is a need to standardize management functionality for multiple reasons. One, Web services themselves are based on open standards. Base services for the platforms, as in security, transactions, and so forth are also getting standardized. It doesn't make sense for management alone to be proprietary. Secondly, open standards enable plug and play of components and ensure a level playing field for software vendors giving customers the best value by avoiding proprietary lock-ins.
This discussion guided us towards an open architecture for a Web services management infrastructure. An analysis of deployment realities, required features, and open standards formed the basis of this architecture.
Standards adopted in the architecture are CIM (Common Information Model) from DMTF (Distributed Management Task Force) and its XML/HTTP bindings in form of the WBEM (Web-Based Enterprise Management) standard. The rationale for choosing these standards is that they exhibit:
- An extensible data model for management information
- Suitability to a Web services management environment (HTTP(S) transport)
- Loose coupling (XML encoding)
- Prevalent adoption across vendors for management of OS, Applications, and so on
The architecture proposed is compatible with existing popular Web services platforms (J2EE-based platforms and .NET) as well as with future platforms. It allows enough scope for vendors providing Web services management products to compete by offering more and more management functionalities based on a framework of open and mature standards.
About the Authors
Pankaj Kothari is a technical lead at Hewlett-Packard, India. He has been involved in designing and developing enterprise middleware and Web services products such as e-speak and HP Application Server. He has also contributed to the architecture and implementation of solutions based on these technologies in various domains for more than five years. He can be reached at firstname.lastname@example.org.
Ravi Trivedi holds a Masters degree in Computer Science from the Indian Institute of Science, Bangalore. He is a Technical Lead at Hewlett-Packard, Bangalore. He is an expert group member for HP in JAXR (JSR 93) and a committer for open source UDDI4j (www.uddi4j.org). He is involved in developing core Web services infrastructure and solutions based on these. He can be reached at email@example.com.
We would like to acknowledge the contributions of Srinivas Varadarajan, Ashish Chitkara, Manoj Seth, Shyam Bijadi, and Jainendra Kumar at Hewlett-Packard, India for their insightful reviews.Disclaimer: The views expressed here are those of the authors and does not necessarily represent that of Hewlett Packard.