Microsoft Transaction Server

Introduction: Microsoft Transaction Server (MTS) is a component-based transaction processing system for building/developing, deploying, and managing high-performance, scalable, and robust enterprise, Internet, and intranet server applications. In addition, MTS allows you to deploy and administer your MTS server applications with a rich graphical tool (MTS Explorer).

It provides services to Component Object Model (COM) software components, to make it easier to create large distributed applications. The major services provided by MTS are Automated Transaction Management, Instance Management (or just in time activation) and Role-based Security.

MTS was first offered in the Windows NT 4.0 Option Pack. In Windows 2000, MTS was enhanced and better integrated with the operating system and COM, and was renamed COM+. COM+ added object pooling, loosely-coupled events and user-defined simple transactions (compensating resource managers) to the features of MTS.

Architecture of MTS: A basic MTS architecture is made up of:

• The MTS Executive (mtxex.dll)
• The Factory Wrappers and Context Wrappers for each component
• The MTS Server Component
• MTS clients
• Auxiliary systems like:
• COM runtime services
• the Service Control Manager (SCM)
• the Microsoft Distributed Transaction Coordinator (MS-DTC)
• the Microsoft Message Queue (MSMQ)
• the COM-Transaction Integrator (COM-TI)

Generally, this is what happens on the Server when a client requests services from a typical MTS component:

1.      Acquire a database connection.

2.      Read the component's state from either the Shared Property Manager or from an already existing object or from the client.

3.      Perform the business logic.

4.      Write the component's changed state, if any, back to the database.

5.      Close and release the database connection.

6.      Vote on the result of the transaction. MTS components do not directly commit transactions, rather they communicate their success or failure to MTS.

Features of MTS: MTS provides the following features:

·         The MTS run-time environment.

·         The MTS Explorer, a graphical user interface for deploying and managing application components.

·         Application programming interfaces and resource dispensers for making applications scalable and robust. Resource dispensers are services that manage non-durable shared state on behalf of the application components within a process.

·         The sample applications that demonstrate how to use the application programming interface (API) to build MTS components, and use scriptable administration objects to automate deployment procedures in the MTS Explorer.

Microsoft Transaction Server APIs: We can use MTS application programming interfaces (APIs) to develop scalable and robust applications that take advantage of the features of the MTS run-time environment, and to automate administration of packages and components.

Automating MTS Administration: We can automate administration of packages and components using the MTS administrative objects. Using Visual Basic, Visual Basic Scripting Edition (VBScript), or any other Automation-compatible language, we can automate procedures in the MTS Explorer ranging from installing a prebuilt package to enumerating through related collections.

Microsoft Transaction Server Sample Applications: In addition to the documentation, MTS includes useful sample applications that are valuable learning tools. We can copy any part of them into our own applications and modify them as necessary.

Throughout the MTS Programmer's Guide, sample code and applications illustrate MTS programming techniques. Many of the files for these applications are included with  installation. We can find the source files for the applications in the \Samples folder of  MTS installation.

MTS provides the following sample applications.

Sample	Description
Sample Bank	Sample Bank is a simple transactional database application that demonstrates how to use the MTS application programming interfaces
Tic-Tac-Toe	Tic-Tac-Toe is a simple multiuser game that shows nontransactional components managing shared state.
Administrative Sample Scripts	The administrative object scripts demonstrate how to automate MTS Explorer procedures using VBScript.