There's a phenomenon I've witnessed again and again in my years building systems. I call it "Guerilla IT." Listen to my description and see if you've witnessed it inside your organization.

You are an IT professional serving your constituency. They are satisfied with your support of their business, but there are a few projects that are lower priority and small enough to fly under your radar. They implement a little "solution" themselves to help get their work done. They are proud of the quick, simple, and cost-effective solution and innocently wonder, "Why can't they get things done this fast?" It works well for them for a little while, but then as the business grows or changes or both, they find they're spending too much time maintaining and enhancing their "little solution". Now they want to hand it over to you to enhance and support.

There are probably a hundred variations of this story, the most relevant of which is grassroots growth of Web services implementations for use inside and outside the enterprise. It is so easy and tempting to expose capabilities as Web services these days that they can pop up almost anywhere. But then as demand grows the support requirements outstrip the original creator's ability to cope and they hit the "scramble threshold." That is, they scramble for someone else to support and maintain their Web services.

Enter the Adults
When enough guerilla projects hit the scramble threshold, the need for real enterprise Web services management becomes abundantly clear. That's when products like Wisiba from Itellix enter the picture.

Wisiba is a new entry in the Web services management marketplace. Wisiba comes in three configurations. The Base configuration provides monitoring, auditing, security, versioning, and provisioning. The High Availability configuration layers on top of the Base and adds SLA management, QoS assurance, load balancing and dynamic routing, failover, contracts, and revenue management. Finally the High Scalability Configuration includes the PowerPlus native proxy server.

The Basics
Wisiba's Base Configuration provides all the standard Web services management capability that you would expect. It acts as a virtual service endpoint that performs the basic services listed above and then routes the request to the physical service for execution. Wisiba can run coresident with the Web service container or run separately as a proxy.

Itellix provides two graphical user interfaces for Wisiba. The first is the Activity Monitor (see Figure 1), which allows the operator to track Web service operations. It is surprisingly functional for such a new product, and I especially like the ability to chart various Web service metrics. The second GUI is the Wisiba management console, which allows for setup and provisioning of Web services. The management console is also core to configuration of service-level agreements, which I discuss in more detail later.

High Availability
Wisiba becomes very interesting when you add the High Availability configuration. Yes, it adds the obligatory load balancing and dynamic routing but with an eye towards the economics of the situation.

jWisiba's logical management model (see Figure 2) starts with the "Service Provider." Service providers list available services and their versions. Service versions are associated with bindings that are a reference to the actual service implementations. A service offering associates a particular service with a payment model, any obligations, and usage. Payments supported are pay as you go (ad hoc), limited time, or limited amount of transactions. Each payment model is customizable. Finally, a provider contract associates a set of service offerings to a particular service provider.

From a service consumer standpoint, a consumer may be a business entity with multiple users. A usage contract contains details such as the service, version, and Quality of Service level contracted. The usage contract also contains the term of the contract and the payment model chosen.

Wisiba tracks all usage towards the contract and this data can be fed into the corporate billing systems. Additionally, Itellix has tied all the QoS and service-level agreement data back to its load-balancing and monitoring systems. For example, if a consumer has exceeded their transaction limit, the monitoring system can notify the consumer, producer, and operator. If the service falls below an established QoS agreement, notifications can also occur. Wisiba can easily spray Web service requests across a bank of machines, but a more realistic load-balancing mechanism would be based on SLAs; Wisiba's unique architecture allows this.

Scalability
Wisiba's High Scalability configuration simply layers the PowerPlus native proxy on top of the other configurations. My first thought when adding an additional box to the request path is "how much is this going to slow my response time?" The unique PowerPlus proxy architecture could alleviate this concern.

Itellix has built the proxy using a Staged Event Architecture first described in a Ph.D. thesis by Matthew David Welsh. This architecture requires a system to be built as a network of stages with requests processed using a combination of thread- and event-based programming models. The architecture also relies on feedback-driven control to allow it to adapt to overload conditions. The result is a system that scales well and is resilient to large variations in load. WSJ is not set up for load testing but Itellix claims they have achieved over 1 million transactions per hour on a commodity dual CPU system.

This architecture also allows Wisiba to profile requests and enqueue them based on predefined SLAs. Top-tier customers can be placed on the highest priority queue where they are served quickly.

Testing
I received the evaluation copy of Wisiba directly from Itellix. The install process was a little bumpy. Make sure to read through the install guide completely before starting as Wisiba will prompt for a number of things as the install proceeds. Don't assume the install defaults will just work. You'll need to provide your own database; the evaluation version requires MS SQL Server. Make sure you create a database and user ID specifically for Wisiba before you start the installation process.

There is a fair bit of setup configuration but it is important and definitely worth it when running in a production environment. Once I installed the product, testing went smoothly. After setup, I was able to provision and access several versions of my services quickly and monitor their progress.

Itellix Company Info
Itellix Software Solutions
101 Prestige Poseidon
139 Residency Road
Bangalore, INDIA-560025
Phone:+91-80-51125501
Fax:+91-80-51125504
Web: www.itellix.com
E-mail: madhukar.srivastava@itellix.com

Licensing Information (2 CPU and under)
Base Configuration: $25,000
High Availability Configuration: $15,000 (add)
High Scalability Configuration: $30,000 (add)

Testing Environment
OS: Windows XP Professional (Service Pack 1)
Hardware: Intel Pentium M Processor (1300MHz) - 1.29 GHz - 1 GB RAM

Conclusion
Wisiba from Itellix sits well in the Web Services Management product space. The product's unique handing of Quality of Service and service-level agreements make it a product that should be considered. So, if your organization hits the "Scramble Threshold", contact Itellix and ask for more information about Wisiba.

• Figure 1
• Figure 2