Microsoft Internet Information Server 4.0


Transaction Server is a component-based transactional processing system that enables developers to build and maintain scaleable Web and server applications. It is a Component Object Model (COM) application that guarantees that transactions, or information exchanges, made by applications developed with Transaction Server will either complete successsfully or abort. If the transaction aborts, the data will remain unchanged, solving the problem of data being corrupted as the result of an incomplete transaction. Transaction Server is installed as a component from the NT 4.0 Option Pack. To install sample files, be sure to go to the subcomponents and check all the items. Transaction server is administered through the MTS Explorer snap-in of the Microsoft Management Console.

MTS Overview

A Transaction is a unit of work that succeeds or fails as a whole. Thes actions have what are called "ACID" propeties. Acid stands for Atomicity, Consistency, Isolation and durability.

Either all changes happen or none happen.
Actions taken as a group do not violate any rules
For actions that execute concurrently, one is executed before or after the other, but not concurrently.
Changes survive the failure of the process.

Three-tier Architecture
Transaction server does not use two-tiered client-server programming but a three tiered logical Architecture consisting of:
The client application consists mostly of a Graphic user interface, and other services are obtained from logical middle-tier servers.
Business/Data Components
Middle-tier components can implement data rules or business rules.
Data Access
This is where the other layers of the architecture access the Database Management System (DBMS).

Microsoft Message Queue Server (MSMQ) Assists Transaction Server by storing messages to applications that are offline, and forwards the message to them when they are back online.

ASP Integration
Active Server pages are based on Transaction Server. Note: a transaction cannot span multiple pages, so objects must be grouped on one ASP page.

Component Object Model (COM)
is a software architecture that allows applications to be built from binary software components, and forms the foundation for higher-level software services, like those provided by OLE.
Distributed Component Object Model (DCOM)
a protocol that enables software components to communicate directly over a network in a reliable, secure, and efficient manner, and is designed for use across multiple network transports, including Internet protocols such as HTTP. DCOM will work with both Java applets and ActiveX components through its use of the Component Object Model (COM).

MTS Explorer

MTS is configured through an MMC snap-in , the MTS Explorer. The Explorer Interface consists of five nodes, Packages Installed, Remote Components, Trace Messages, Transaction List, and Transaction Statistics.
Packages Installed
Shows all local Packages, sets of components that perform related application functions.
Remote Components
Shows components on other servers.
Trace Messages
Views messages that include the status of such MTS activities as startup and shutdown.
Transaction List
Lists the properties of the running transactions.
Transaction Statistics
Tracks transaction performance.

An MTS Sample

To see MTS in action you need to do the following:
1. Install the Transaction Server Development Subcomponent of the Transaction Server Component from the NT4.0 Option Pack files.
2. Install SQL Server 6.5 from the option Pack files and start the SQL server.
3. Configure an ODBC data source in the ODBC Applet of the Control Panel. In the User DSN property sheet, click Add, select SQL Server and click Finish. In the Name field type MtxSamples and select (local) in the Server menu. Click next and OK through the remaining dialog boxes, accepting the defaults, and close the Control Panel.
4. Open the MTS Explorer, expand the nodes and click on Transaction Statistics. Leave this window open.
5. At the Windows NT Server 4 desktop click Start >> Programs >> Windows NT 4.0 Option Pack >> Microsoft Transaction Server >> Bank Client.
6. Tile this window with the MTS Explorer Transaction Statistics. Click the submit button in the Bank Client dialog box and notice the activity in the Transaction Statistics. A deposit of one dollar has been made to the account and shows up in the statistics as a commited tranaction. Submit additional transactions and view the results.