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March 8, 1999

App Server With Better Management

Metaserver targets Web development as virtual server

By Ron Copeland

etaserver Inc. plans a May release for version 2.0 of its application server and development environment, which provides enhancements to the product's wizard-based workflow and administrative tools. The tools allow distributed system resources to be more easily linked, to form a virtual application.

Metaserver aims to simplify Web development and application integration by automating many steps that previously required custom coding. The product is especially well-suited to financial and insurance companies that maintain lots of legacy data, which must be accessed by more modern applications.

Metaserver is a virtual application server that--rather than running or processing application requests directly on the Web server--delegates processing to any number of designated computers residing on the network. Metaserver coordinates application processing, as opposed to actually hosting it. This coordination mechanism is based on Scientific Computing Associates' shared network memory model. Metaserver was spun off from SCA in 1996.

Server Built On Shared Memory

Metaserver is built on a virtual shared memory model, a proven technical approach to distributed processing. Shared memory leverages the power and intelligence of multiple devices on a network.

Metaserver's architecture is similar in concept to the architecture of a traditional computer model consisting of memory, instruction data, system bus, and processing units. With Metaserver, the virtual shared memory, which equates to memory and instruction data, combines with the Internet--which is comparable to the system bus--to process a user's request. Metaserver application components equate to high-level processing units such as a mainframe. Together, these processing elements provide a robust way for executing client requests for application processing over the Web.

--Ron Copeland

The unique characteristic of this technology is the way it performs process flow within an application based upon shared network memory, says David Kelly, VP of application strategies for the Hurwitz Group, a market research firm. "Metaserver's intent is not to build up a centralized application server, but to be able to use shared memory in multiple servers across a network to distribute the processing and the connectivity among an organization's resources," Kelly says.

Metaserver has three major components: the MetaServe server software; MetaLink connectors to external systems and applications; and MetaTasks, the actual program execution elements. Front-ending the Metaserver development environment is a drag-and-drop graphical user interface that lets developers easily diagram and create an application. Together, these components provide development and deployment software that lets a Web browser transparently access distributed, system application resources scattered throughout an enterprise network.

Metaserver is well-suited for IT shops that don't have hundreds of sophisticated object-oriented Java programmers available. That's because Metaserver takes a business-process, visual diagramming approach to the project.

"You're going to find it much easier to take Cobol developers or business analysts to create a new application or resequence an existing one," Kelly says. "From that perspective, I view it as sort of an enterprise RAD tool, letting users quickly create and modify applications without a specific in-depth object-oriented or specific language skill set."

Adds Dave Blodgett, the enterprise systems and middleware manager at the Mashantucket Pequot Museum & Research Center in Mashantucket, Conn., "With Metaserver, we could easily take different applications and access the same data without having to write all these custom interfaces."

The museum had a set of graphic images that it needed to share among multiple applications--initially a library-management system and a collections-management system. The images resided on EMC's Celerra Media Server. The media server had a set of APIs associated with it, so some coding was required to read, write, and maintain images on the media server. The organization needed to make it possible for these different applications to use the media server APIs to access the same set of images. Metaserver gave the applications seamless access to those images, Blodgett says.

The MetaServe software, which runs on Unix or Windows NT servers, provides parallel and distributed processing, fault tolerance, load balancing, failover and automatic restart, and the ability to dynamically reconfigure an application.

The server uses MetaLinks--connectors or custom software templates--to bridge to existing applications, databases, or mainframe system resources.

MetaTasks, which can run in parallel, are used to define the application's distributed execution process. The MetaTasks contain instructions about which resources are to be used and the order in which they must be executed. MetaServe monitors and automatically load balances requests for service to multiple systems and, in the event of a fault or error, redirects the request.

Since MetaTasks are developed and maintained separately from the application logic, upgrading an application is relatively easy.

"If we have another application that needs to play in this environment, it will be almost a plug-in to Metaserver," says the Mashantucket Pequot Museum's Blodgett. "The back end is already written for reading and writing the images to the media server. We can easily plug in Web-enabled access to images."

With Metaserver, the complex, performance-related features and functionality to build a Web application are available right out of the box, says Kathleen Garlasco, Metaserver's sales VP. "Metaserver effectively takes the build out of the Web application server strategy," adds Garlasco. Once users have created the MetaLinks, they use the visual programming tool to drag and drop them in the order needed to execute to fulfill a specific business request, such as trading stocks via the Internet.

Reusability is also an important dividend. When a user needs to create a MetaLink to an Oracle database with a very different set of instructions from one previously built, only minor modification will be needed. The original SQL link can be used as a template for subsequent links.

Several MetaLinks are supplied, but new MetaLinks can be created using wizards, templates, or APIs that provide language-level bindings. MetaLinks support Corba and Microsoft's DCOM component standards as well as Java, JavaBeans, ActiveX, C, C++, and Perl programming languages. Metaserver has a well-defined API for connecting to existing mainframe and other legacy applications.

Metaserver also features a centralized management console for administering the distributed application. It's used to display the current state of all the MetaTasks that are executing. Version 2.0 also lets it access control rules for tasks stored in a central repository.

The ideal Metaserver customer is an organization that has significant technology investments but needs to continue investing in emerging Internet technologies. Metaserver can help a company get a Web application up more quickly than could be done with traditional coding approaches.

While Metaserver delivers much in the way of development and integration, it's among the higher-priced application servers on the market, ranging from $75,000 to $125,000. Design and implementation services are included in the price of the software.