Second, users can ease into it by migrating their VB code from the client to the server. After partitioning the business logic from the presentation logic (admittedly a nontrivial task), the business logic must be wrapped in ActiveX, and any idiosyncratic state management, such as global static variables, must be converted to use resource dispensers. Drop the new service package into MTS, and you're in business. MTS will spawn instances of your service to multiple threads and manage database connections as more thin clients request the service.

Third, MTS is built around a modern distributed component model--the Distributed Component Object Model (DCOM). Although it is still vendor-specific--and that vendor is Microsoft--there is widespread vendor support for DCOM. When combined with MTS, DCOM lets developers partition their monolithic applications into reusable transactional components. SAP has even based its R/3 co mponent standard on DCOM, and there are rumors that the vendor may base the next generation of SAP R/3 on MTS.

Of course, as with most Microsoft "version 1.0" technology, there's still a lot to be filled in. The thread management is primitive, there is no server-to-server load-balancing, full two-phase commit is supported only by SQL Server and distributed directory services like Active Directory, which are required for large-scale deployment of MTS services, won't be available until NT 5.0.

MTS versus OTS Although Microsoft is first out of the block with a next-generation transaction server, others are not far behind. Many of the major RDBMS vendors have waved the white flag of surrender and announced TP-heavy products. Last fall, Oracle announced its Network Computing Architecture (NCA), which will implement the Object Transaction Server (OTS) specification of Common Object Request Broker Architecture (CORBA). Earlier this year, Sybase announced its Jaguar Component Transaction Server (CTS), which will be an MTS work-alike on NT and will use JavaSoft's Java Transaction Server (JTS), a Java version of OTS, on Unix. Recently, IBM threw its hat into the ring with its CB (Component Broker) Connector, which will also implement CORBA's OTS. Expect to see Informix back away from its disastrous "everything is a blade" strategy, and adopt a three-tier TP-heavy product.

In addition to the transaction servers announced by the recently converted RDBMS vendors, traditional TP monitor vendors are evolving their products into component-oriented transaction servers. BEA Systems is integrating its TUXEDO TP monitor with Object Broker, the object request broker (ORB) it acquired from Digital. Expect to see NCR adding an OTS personality to its Top End product.

Even smaller players are jumping on the transaction server bandwagon. Kiva Software offers a Web-oriented transaction server that is the engine behind the Internet Shopping Network and Travelocity. Visigenic plans to offer an OTS as part of its ORB. An d Iona is offering an OTS based on IBM's Encina engine.

Where Do We Go From Here? Clearly, the battle has shifted from RDBMS/stored procedure-based TP-lite versus TP monitor based TP-heavy to a battle between DCOM-based MTS versus CORBA-based OTS. MTS is certainly ahead in price, ease of entry and simplicity. OTS is ahead in scalability and cross-platform support, given that the traditional TP monitor vendors are behind it. By the year 2000 or so, expect to see MTS dominate at the low-to-midrange and OTS to dominate at the high end.

Of course, besides the current lack of development and management tools, which is common to all new technologies, both MTS and OTS are missing one critical component: integrated business quality messaging (BQM). I'll have more to say about BQM in an upcoming column, but suffice it to say that transaction servers must evolve from a highly synchronous paradigm to a highly asynchronous one to support the k ind of business-to-business transaction processing envisioned b y the concept of extranets. Microsoft has announced plans to integrate its upcoming message queuing middleware, code-named Falcon, into MTS. And the Object Management Group is considering proposals for integrating message queuing middleware like IBM's MQSeries into CORBA and OTS. The TP wars are over.

Nick Gall is a program director with the META Group's Open Computing & Server Strategies service. He can be reached at nick.gall@metagroup.com.