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Wednesday March 20 2002 Web Services and Logistics Web Services and your car In this article, we take a look at the application of Web Services in the area of logistics. Our case study offers an insight into a slightly unusual aspect of logistics, in that it doesn't pertain to the shipping of large quantities of goods. Rather, we see how Web Services are getting into our cars. The information upon which our discussion is based comes from interviews carried out with Wade William from Networkcar, and examines the use of Web Services in their real time processing of diagnostic data from vehicles. Networkcar Networkcar (http://www.networkcar.com/) is a car information service company that collects real time diagnostic, performance, and GPS data from vehicles. The information is transferred in real-time over the public Internet by wireless technology, from the vehicle to Networkcar. The information is gathered from the car's on-board computer through the CAReader device, which combines a GPS location system, wireless Internet connection, and interface for the car computer. The information is available for the owner of the car, and can also be made available to selected technicians. When a problem is registered with the onboard computer, the owner can be notified by an automatic email alert. Along with this warning, your chosen repair technician can monitor the progress of your car to reduce the time it spends in servicing and repairs, reducing the amount you spend on it.
The provision of the Networkcar services is somewhat bespoke by nature, given that it involves the installation of a small device (CAReader) to your car to monitor its status. As a result of being individually tailored in this way, the price is individually tailored, increasing as more services are subscribed to. There is an installation fee, together with a regular subscription fee based on the services required. Since these services are generally bought through another sales channel, such as the American Automobile Association for example, the costs would be tagged on to that of their normal membership. This services-oriented approach allows the customer to get the degree of functionality and complexity that meets their specific needs. With the fine-grained approach, a customer can subscribe to, for example, just the oil and brakes tracking facility. All the functionality of the Networkcar system is typically accessed through a Java client supplied by Networkcar; as we will see, though, the same functionality is being exposed as Web Services. These Web Services can be called from within customer e-business applications, providing complete solution integration and automation. The architecture employed for this Web Services solution is based on a servlet to handle the requests for Web Services published using WSDL; the information is tapped into at the client end with another J2EE application. With the move to standards based Web Services, however, Networkcar will be able to offer their services to customers with no support for a J2EE client. We'll examine the scope of the actual services shortly. Idea Origination One of Networkcar's fleet management clients wanted to retrieve GPS coordinate and diagnostic data for their vehicles on a regular basis. After some discussion with the clients, Wade William, technical lead behind the project, discovered that the client could handle XML documents. It is worth noting that this discussion was held while Networkcar was still running on WLS (WebLogic Server) 5.1, which had no built-in support for what have since been termed as Web Services. Specifically, there was no support for SOAP, WSDL, or UDDI. Undaunted, Wade and his team created a small servlet which accepted XML requests, authenticated the user via credentials contained in the document, then satisfied the request and returned an XML response. In the original version of the application, this was implemented using JSPs and custom tags. Shortly thereafter, Networkcar began the conversion from WLS 5.1 to WLS 6.1. At this point, they converted all of those "hand-built" Web Services into true Web Services (stateless session beans, SOAP servlets, WSDL, etc.) using the tools provided by BEA. Web Services Description Let us now look at the services offered by Networkcar. We can group the Web Services into four categories:
We will examine these a category at a time, after defining who uses them. We can split the users of these services into two groups, Customers and Clients. A customer, in this case, is the person who actually drives the car and subscribes to a personalized car management program. A client, on the other hand, is a company whose application uses the Networkcar Web Services direct - they may choose to pass this benefit on to their customers (as in an addition to AAA platinum membership, for example), or use it entirely for their own purposes (as in the case of the fleet management company). Vehicle Information Update Services This category of services deals with the updating of the principal information available through the Networkcar service. The CAReader device is the principal user of these Web Services, which update the information held by the system, although they can also be called by the client application to force the information to be updated. The services provided perform the following functions: Each service provides the system with an update to part of the information gathered by the wireless device. For example, the Update Miles Per Gallon service updates the information on how many miles the vehicle is averaging per gallon of fuel. Networkcar Web Services Calling these services, as you would expect, gives the client or customer the ability to begin to interface with the Networkcar system. Once logged on, calling the Web Service provides the client with a list of customer information, including such things as emergency contact details, blood type, address, etc. Notice that the Networkcar system operates a single sign on policy - once you've signed on to use one set of services, any other services you are subscribed to will be available for you as well, without having to sign in again. Vehicle Information Services This third category of services provides a client, such as a roadside assistance provider, with access to the raw data from the vehicle. This allows them to process the information at their own pace, on their own system. The Get Vehicle Data service, for example, allows the client to obtain historical data for the vehicle in question, including engine performance, fuel capacity, battery charge, etc. GPS Information Service This final category of services enables the client (fleet managers, AAA, the Police, etc.) to obtain GPS location information for the vehicle. Once the client has logged in to the system, and they can request the GPS location of the vehicle. Knowing where the vehicle is can prove invaluable in theft retrieval situations. If a vehicle monitored by Networkcar is reported as stolen, it is a simple matter to call the GPS Info service and let the authorities know where the vehicle is. Benfits from Web Services People don't just switch their applications to using the Web Services architecture because it gives them a snappy title; there has to be a tangible benefit. There are two types of benefit that will be looked for, technical and business. Technical Benefits The technical benefits an organization can reap from utilizing the Web Services architecture can be grouped into those arising from Standards based development, and those arising from using Application servers.
Business Benefits The use of Web Services allows Networkcar to focus on its business, instead of application integration. Before making use of Web Services, any enterprise wanting to use the Networkcar services would have had to spend months on application integration. With less expenditure on application integration, more money can be spent on expanding the business, reaching more customers, and increasing profits. Conclusion Using XML to provide an existing service to a new customer opened the gate to the move to Web Services. The innately component oriented J2EE base for the system helped enormously. With Web Services in place, new horizons open up. The adoption of fine-grained Web Services gives Networkcar flexibility when packaging its services. Because their client can select each service individually, Networkcar can treat their Web Services as commodities. Given that Networkcar are profit driven in their use of Web Services, not just cost-minimal driven, this allows them to offer an individual package for no extra cost than a pre-selected package of services. The extended PDF version of this article is available now. Web Services and Logistics by John
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