Web Services

         Web services is nothing but a resource through which you can convert your application into web application, also it helps data transfer between various platforms and applications and the most recommended format of transferring data is XML. XML has been recognized by W3C to be used exclusively for web services, in other words data is carried out in XMLs.

        Web services basically consists of three elements :

1. SOAP

2. WSDL

3. UDDI

SOAP : SOAP is Simple Object Access Protocol, which enables the transfer of data between various platforms and different languages, so this becomes the main part of web services. It uses HTTP protocol for the transfer of data.

SOAP basically consists of 

• Envelope
• Header
• Body
• Fault

Envelope : Envelope is the root element of the SOAP message, it consists soap:xmlns namespace which has default value of : 

---------------------------------------------------------------------------

"http://www.w3.org/2001/12/soap-envelope"

---------------------------------------------------------------------------

Example :
---------------------------------------------------------------------------------------------------------

<?xml version="1.0"?>

<soap:Envelope xmlns:soap="http://www.w3.org/2001/12/soap-envelope"
soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">

............
Messages that you want to transfer

............
</soap:Envelope>

---------------------------------------------------------------------------------------------------------

If any namespace other than soap:xmlns is used, it will not allow the transfer and generate an error.

SOAP encoding Style attribute : It is the basic encoding style used in the SOAP

soap:encodingStyle="URI".

Header : Header is the first element of Envelope element in the SOAP message. It contains three attributes : 

• mustUnderstand
• actor
• encodingStyle

Body : This contains the actual message that will be transferred.

------------------------------------------------------------------------------------------------------------

<?xml version="1.0"?>
<soap:Envelope
xmlns:soap="http://www.w3.org/2001/12/soap-envelope"
soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">

<soap:Body>
  <m:GetPrice xmlns:m="http://www.w3schools.com/prices">
    <m:Item>Apples</m:Item>
  </m:GetPrice>
</soap:Body>

</soap:Envelope>

------------------------------------------------------------------------------------------------------------

Fault : It is an optional element and it is used to indicate error messages.

WSDL : Web Services Description Language, is other part of web services which is used to locate and describe the application that is converted into web application. It's simply a link that takes you to the application, in other words you convert the data that is inter-operable between different platforms using SOAP and WSDL takes you to that data.

UDDI : Universal Description, Discovery and Intergration, is a kind of directory for storing the information about web services it transfers data via SOAP.

If you want to learn more about Web Services refer : 

http://w3schools.com/webservices/ws_why.asp

MIRA: World's fastest supercomputer

Mira. That is her name. She is the supercomputer IBM Corp is building for US department of energy's Argonne National Lab. IBM says, Mira will make more than 10 quadrillion (1 quadrillion = 1,000 trillion) calculations a second, four times faster than China's Tianhe-1A, currently considered the fastest. The world's fastest supercomputer-tobe will make its debut next year.

the above picture shows world's biggest supercomputer: worm computer;
Reports on the world's fastest supercomputer:-
According to reports, if the entire population of the US does one calculation per second, it will take them a year to run as many calculations as Mira can do in one second. Named after the Latin root to wonder or marvel, Mira is expected to cost roughly $50 million, according to reports. But IBM doesn't comment on the price of its client's systems, says Herb Schultz, market manager for IBM Deep Computing. Neither has Argonne National Lab made that information available to date. Argonne's current supercomputer Intrepid makes more than 500 trillion calculations a second. Mira will be 20 times faster.



Schultz, the market manager told The Economic Times on Sunday: "Many systems can do the same calculations, but Mira can do them faster and do more per unit time. Because of that, a scientist on Mira can gain greater insight by virtue of examining more time steps in models and simulations." IBM expects Mira to help department of energy (DOE) to do several complex calculations and be a "strong science and technology engine that will fuel national innovation". "Our goal is not to develop a system that is number one on a list. Our goal is to help Argonne advance its research, which will contribute significantly to society," says Schultz. Argonne National Lab is one of USDOE's oldest and largest labs for science and engineering research.


Advantages:-
The 10-petaflop Mira, which falls under IBM's "Blue Gene/Q" series of supercomputers, will be made available to scientists from industry, academia and government research facilities around the world, according to reports. It will mean a lot to businesses, too. Says Dan Olds, an analyst at Gabriel Consulting Group in Beaverton, Oregon: "Wall Street will use those computers to analyse their portfolios to see what will happen if interest rates do this or that. [Pharmaceutical] retailers can use them to track cold and flu season, so they know how much tissue or Nyquil to stock in particular stores at particular times."