Migrating from applications to services: A .Net technology primer

A programming language called C#, a Meta language XML and a range of servers add some meat to Microsoft .NET strategy with XML occupying the center stage. An overview

Last year Microsoft unveiled its .NET strategy, and true to its marketing prowess, it was immediately regarded as vaporware. Since then, it has added many components to its .NET strategy, with XML taking center stage. Before we dwell more into the technicalities of this framework, lets understand the business logic behind the model. Today, businesses are faced with continuous challenges prompted by mergers and acquisitions, changing consumer trends, and shifting demographics among others.

Against this backdrop .NET talks about a framework where software is a Web service which operates through SOAP (Simple Object Access Protocol) using XML for messaging and storage. The clear advantage would be that, being open standard, services and plug-able businesses would not have to bother about integration issues and speed of deployment.

It seems we developers can do just about anything with Microsoft's .NET technical strategy. It can be used for developing an internal system i.e. client-server system for automating a business process (C#, VB.Net); for developing a business site (Asp.NET); for integration between businesses (Biztalk Server); for giving a Web interface to existing businesses (Commerce Server 2000); for having mobile touch points in new/existing sites (Mobile Information Server), selling services through an exposed Web Services model.

WEB SERVICES

Microsoft's pitch about Web services is as follows: The .NET XML Web services are an integrated set of building block services, including Passport (for user authentication) and services for file storage, user preference management, calendar management, and many other functions. XML Web services allow applications to share data and invoke capabilities from other applications across any platform or operating system.

Microsoft is now repackaging its Web-based applications, its Passport Internet authentication technology and its MSN Messenger client for instant messaging, as horizontal Web services building blocks, under its Hailstorm initiative.

. NET Server Range

A total of eight server products (See Box), form the core part of the .NET server group, as part of the larger .NET development framework released by Microsoft last year. Some products come from a family offering earlier known as Back Office.

A detailed article elsewhere in this issue (page 40) talks about the product features in detail and how .NET servers fall into the range.

C#

Pronounced C Sharp, is a programming language derived from C/C++. Contrary to popular notion, it is not a copy of Java, but inspired by it in terms of design. On a high level, we will point out when the syntactical structures are the same, and spend time talking about when they are different. There are a few syntactical "extras" in C# that do not have equivalents in Java as I found out.

Java has a couple of primitive data types: byte, char, int, long, floats, double. Primitives are the basic building blocks of Java; they are the smallest "unit." What usually annoys most programmers is that, whereas all objects in Java extend from java.lang.Object, primitives do not extend from anything. This means that any class that operates on objects will not work with primitives. The primitives must be mapped into the object model in order to use it. This is not the case with C#.

C# uses the .NET object/type system so that C# programs may inter-communicate with other .NET languages without having type confusion for example, the type int is an alias to System.Int32 which in turn ultimately extends from System.Object. This means that the primitive, or simple types in C# function just like any other object.

It supports a fairly rich type system termed "Common Language Specification (CLS)" ensuring interoperability with components written using other CLS compliant languages such as Visual Basic.NET. Since C# has been created for the .NET platform it supports events and properties as part of its language syntax, and it also supports creation of Web services natively.

Because of its component structure it also provides migration avenues from languages like Smalltalk.

Where do you want to go tomorrow?

While Microsoft is building a big picture of how and why developers and corporations should migrate to the .NET platform, it's still premature as the framework is still evolving. While the Web Services front-end is open, and soon to be standardized it's the enterprise level system integration that is still getting locked into proprietary technologies e.g. MSMQ Vs JMS, and not to forget ASP.NET. The hyper EAI environment, which Microsoft paints, is still infested with proprietary code lock-ins.

On the other hand, Sun with its newly released set of APIs, is fast catching up on the Web Services front and given its track record in the server side arena, it's bound to catch up.

Microsoft recently entered the enterprise space and already it has a very bankable offering: Biztalk Server 2000, which leverages the power of XML. In the Indian context, a disturbing trend that is being is noticed is that enterprises are prototyping their application workflows using these products and eventually using competing products for deployment.

It needs to be seen how Microsoft will make that transition from a desktop company to an enterprise company. Market concerns are with regard to server version support, as enterprises cannot migrate their server products every year. Also, under its C# initiative the CLR initiative is not available for the non-windows environment although the initiation has already taken place.

Till then, switching to Windows XP wouldn't be a bad choice.

(The author is a Strategist with Plexus Technologies. The views expressed here are his own. Write to him at bhavishsood@netscape.net)

XML Web Services Foundation
Simple, Open, Broad Industry Support
Publish, Find, Use Services : UDDI
Service Interactions : SOAP
Universal Data Format : XML
Ubiquitous Communications : Internet

<<  >>