Over the years, our computing lifestyles have changed. Today, everyone sees the value of
the Internet, and our computing lifestyle is becoming more and more dependent on Web-
based services. Personally, I love to shop, get traffic conditions, compare products, buy
tickets, and read product reviews all via the Internet.

However, I’m finding that there are still many things I’d like to do using the Internet that aren’t
possible today. For example, I’d like to find restaurants in my area that serve a particular
cuisine. Furthermore, I’d like to be able to ask if the restaurant has any seating for, say, 7:00
p.m. that night. Or if I had my own business, I might like to know which vendor has a
particular item in stock. If multiple vendors can supply me with the item, I’d like to be able to
find out which vendor offers the least expensive price for the item or maybe which vendor
can deliver the item to me the fastest.
Services like these don’t exist today for two main reasons. The first reason is that no
standards are in place for integrating all this information. After all, vendors today each have
their own way of describing what they sell. The emerging standard for describing all types of

information is Extensible Markup Language (XML). The second reason these services don’t
exist today is the complexity of developing the code necessary to integrate such services.
Microsoft has a vision in which selling services is the way of the future—that is, companies
will offer services and interested users can consume these services. Many services will be
free; others will be available through a subscription plan, and still others will be charged per
use. You can think of these services as the execution of some business logic. Here are
some examples of services:
 §Validating a credit card purchase
 §Getting directions from point A to point B
 §Viewing a restaurant’s menu
 §Booking a flight on an airline, a hotel room, or a rental car
 §Updating photos in an online photo album
 §Merging your calendar and your children’s calendars to plan a family vacation
 §Paying a bill from a checking account
 §Tracking a package being shipped to you 
 could go on and on with ideas for services that any company could implement. Without a
doubt, Microsoft will build some of these services and offer them in the near future. Other
companies (like yours) will also produce services, some of which might compete with
Microsoft in a free market.
So how do we get from where we are today to a world in which all these services are easily
available? And how do we produce applications—HTML-based or otherwise—that use and
combine these services to produce rich features for the user? For example, if restaurants
offered the service of retrieving their menu, an application could be written to query every
restaurant’s menu, search for a specific cuisine or dish, and then present only those
restaurants in the user’s own neighborhood in the application.
          Note
                    To create rich applications like these, businesses must offer a programmatic
                    interface to their business logic services. This programmatic interface must
                    be callable remotely using a network, like the Internet. This is what the
                    Microsoft .NET initiative is all about. Simply stated, the .NET initiative is all
                    about connecting information, people, and devices.
Let me explain it this way: Computers have peripherals—mouse, monitor, keyboard, digital
cameras, and scanners—connected to them. An operating system, such as Microsoft
In this new world, the services (or peripherals) are now connected to the Internet.
Developers want an easy way to access these services. Part of the Microsoft .NET initiative
is to provide this development platform. The following diagram shows an analogy. On the
left, Windows is the development platform that abstracts the hardware peripheral differences
from the application developer. On the right, the Microsoft .NET Framework is the
development platform that abstracts the XML Web service communication from the application developer.
Although a leader in the development and definition of the standards involved in making this
new world possible, Microsoft doesn’t own any of the standards. Client machines describe a
server request by creating specially formatted XML and then sending it (typically using
HTTP) over an intranet or the Internet. Servers know how to parse the XML data, process
the client’s request, and return the response as XML back to the client. Simple Object
Access Protocol (SOAP) is the term used to describe the specially formatted XML when it is
sent using HTTP.
The following figure shows a bunch of XML Web services all communicating with one
another using SOAP with its XML payload. The figure also shows clients running
applications that can talk to Web services and even other clients via SOAP (XML). In
addition, the figure shows a client getting its results via HTML from a Web server. Here the
user probably filled out a Web form, which was sent back to the Web server. The Web
server processed the user’s request (which involved communicating with some Web
services), and the results are ultimately sent back to the user via a standard HTML page.
communication from the
addition, the computers providing the services must be running an operating system that
is listening for these SOAP requests. Microsoft hopes that this operating system will be
Windows, but Windows isn’t a requirement. Any operating system that can listen on a
TCP/IP socket port and read/write bytes to the port is good enough. In the not too distant
future, mobile phones, pagers, automobiles, microwave ovens, refrigerators, watches, stereo
equipment, game consoles, and all kinds of other devices will also be able to participate in
this new world.
On the client or application side, an operating system must be running that can read/write to
a socket port to issue service requests. The client’s computer must also be capable of
supporting whatever features the user’s application desires. If the user’s application wants to
create a window or a menu, the operating system must provide this functionality or the
application developer must implement it manually. Of course, Microsoft hopes that people
will write applications that take advantage of the rich feature set in Windows, but again,
Windows is a recommendation, not a necessity.
the
What I’m trying to say is that this new world will happen whether Microsoft is a part of it or
not. Microsoft’s .NET initiative is all about making it really easy for developers to create and
access these services.
Today, we could all go write our own operating system and create our own custom Web
servers to listen and manually process SOAP requests if we wanted to, but it’s really hard
and would take a long time. Microsoft has taken on all this hard work for us, and we can just
leverage Microsoft’s efforts to greatly simplify our own development efforts. Now we, as
application developers, can concentrate and focus on our business logic and services,
leaving all the communication protocols and plumbing to Microsoft (who has a lot of
developers that just love to do this nitty-gritty stuff).

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