In 1993 the U.S. Department of Commerce, in conjunction with several public and private entities, created InterNIC to maintain a central database that contains all the registered domain names and the associated IP addresses in the U.S. (other countries maintain their own NICs (Network Information Centers) -- there's a link below that discusses Canada's system, for example). Network Solutions, a member of InterNIC, was chosen to administer and maintain the growing number of Internet domain names and IP addresses. This central database is copied to Top Level Domain (TLD) servers around the world and creates the primary routing tables used by every computer that connects to the Internet.

Every website on the internet has a unique IP address assigned to it, made up of a series of numbers. These numbers tell the domain name system (DNS) to locate the corresponding website. As we are humans and not computers, IP addresses are difficult to remember and so words are used instead. These words are known as the domain or URL. The DNS looks at the domain name and translates it into an IP address.
A web service is any piece of software that makes itself available over the internet and uses a standardized XML messaging system. XML is used to encode all communications to a web service. For example, a client invokes a web service by sending an XML message, then waits for a corresponding XML response. As all communication is in XML, web services are not tied to any one operating system or programming language—Java can talk with Perl; Windows applications can talk with Unix applications.
Secondly, the client application needs to know what the web service actually does, so that it can invoke the right web service. This is done with the help of the WSDL, known as the Web services description language. The WSDL file is again an XML-based file which basically tells the client application what the web service does. By using the WSDL document, the client application would be able to understand where the web service is located and how it can be utilized.

Web services architecture: the service provider sends a WSDL file to UDDI. The service requester contacts UDDI to find out who is the provider for the data it needs, and then it contacts the service provider using the SOAP protocol. The service provider validates the service request and sends structured data in an XML file, using the SOAP protocol. This XML file would be validated again by the service requester using an XSD file. 

A developer using a top-down model writes the WSDL document first and then uses a code generating tool to produce the class skeleton, to be completed as necessary. This model is generally considered more difficult but can produce cleaner designs and is generally more resistant to change. As long as the message formats between the sender and receiver do not change, changes in the sender and receiver themselves do not affect the Web service. The technique is also referred to as contract first since the WSDL (or contract between sender and receiver) is the starting point.[6]


 - The message parameter in the WSDL definition is used to define the different data elements for each operation performed by the web service. So in the example above, we have 2 messages which can be exchanged between the web service and the client application, one is the "TutorialRequest", and the other is the "TutorialResponse" operation. The TutorialRequest contains an element called "TutorialID" which is of the type string. Similarly, the TutorialResponse operation contains an element called "TutorialName" which is also a type string. 

The end user verifies that the whois admin contact info is correct, particularly the email address; obtains the authentication code (EPP transfer code) from the old registrar, and removes any domain lock that has been placed on the registration. If the whois information had been out of date and is now updated, the end-user should wait 12–24 hours before proceeding further, to allow time for the updated data to propagate. 

A web service always hides the internal complexity of the service to its clients. For an example, an airliner which is selling tickets via a third party portal is only gathering end user info via a web service and in return it is providing ticket. The portal which is selling ticket doesn't have to bother about the internal complexity of the airlines ticket reservation systems.
Loosely Coupled – Loosely coupled means that the client and the web service are not bound to each other, which means that even if the web service changes over time, it should not change the way the client calls the web service. Adopting a loosely coupled architecture tends to make software systems more manageable and allows simpler integration between different systems.
Functional and non-functional testing of Web services is done with the help of WSDL parsing. Regression testing is performed by identifying the changes made to upgrade software. Web service regression testing needs can be categorized in three different ways, namely, changes in WSDL, changes in the code, and selective re-testing of operations. We can capture the above three needs in three intermediate forms of Subset WSDL,[7] namely, Difference WSDL (DWSDL), Unit WSDL (UWSDL), and Reduced WSDL (RWSDL), respectively. These three Subset WSDLs are then combined to form Combined WSDL (CWSDL) that is further used for regression testing of the Web service. This will help in Automated Web Service Change Management (AWSCM),[10] by performing the selection of the relevant test cases to construct a reduced test suite from the old test suite. [11]
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SOAP is known as a transport-independent messaging protocol. SOAP is based on transferring XML data as SOAP Messages. Each message has something which is known as an XML document. Only the structure of the XML document follows a specific pattern, but not the content. The best part of Web services and SOAP is that its all sent via HTTP, which is the standard web protocol.
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In 1993 the U.S. Department of Commerce, in conjunction with several public and private entities, created InterNIC to maintain a central database that contains all the registered domain names and the associated IP addresses in the U.S. (other countries maintain their own NICs (Network Information Centers) -- there's a link below that discusses Canada's system, for example). Network Solutions, a member of InterNIC, was chosen to administer and maintain the growing number of Internet domain names and IP addresses. This central database is copied to Top Level Domain (TLD) servers around the world and creates the primary routing tables used by every computer that connects to the Internet.
It is unwise to attempt to transfer a domain immediately before it expires. In some cases, a transfer can take up to 14 days, meaning that the transfer may not complete before the registration expires. This could result in loss of the domain name registration and failure of the transfer. To avoid this, end users should either transfer well before the expiration date, or renew the registration before attempting the transfer.[4]
The end user verifies that the whois admin contact info is correct, particularly the email address; obtains the authentication code (EPP transfer code) from the old registrar, and removes any domain lock that has been placed on the registration. If the whois information had been out of date and is now updated, the end-user should wait 12–24 hours before proceeding further, to allow time for the updated data to propagate. 

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Functional and non-functional testing of Web services is done with the help of WSDL parsing. Regression testing is performed by identifying the changes made to upgrade software. Web service regression testing needs can be categorized in three different ways, namely, changes in WSDL, changes in the code, and selective re-testing of operations. We can capture the above three needs in three intermediate forms of Subset WSDL,[7] namely, Difference WSDL (DWSDL), Unit WSDL (UWSDL), and Reduced WSDL (RWSDL), respectively. These three Subset WSDLs are then combined to form Combined WSDL (CWSDL) that is further used for regression testing of the Web service. This will help in Automated Web Service Change Management (AWSCM),[10] by performing the selection of the relevant test cases to construct a reduced test suite from the old test suite. [11]

Synchronous or Asynchronous functionality- Synchronicity refers to the binding of the client to the execution of the service. In synchronous operations, the client will actually wait for the web service to complete an operation. An example of this is probably a scenario wherein a database read and write operation are being performed. If data is read from one database and subsequently written to another, then the operations have to be done in a sequential manner. Asynchronous operations allow a client to invoke a service and then execute other functions in parallel. This is one of the common and probably the most preferred techniques for ensuring that other services are not stopped when a particular operation is being carried out.


If you're interested in additional services like email hosting or if you require support in French, ensure that the Registrar you choose meets those needs. You can use the filters provided in our search to see which Registrars offer the services you require. Remember, if you registered your .CA domain name as an individual you have free WHOIS privacy protection already included.

Unlike traditional client/server models, such as a Web server/Web page system, Web services do not provide the user with a GUI. Web services instead share business logic, data and processes through a programmatic interface across a network. The applications interface, not the users. Developers can then add the Web service to a GUI (such as a Web page or an executable program) to offer specific functionality to users.
Web services are almost like normal a web page. The difference is that they are formatted to make it very easy for a program to pull data from the page, to the point of probably not using any HTML. They generally also are more reliable as to the consistency of the format, may use a different formal process to define the content such soap or raw xml, and there is often also a descriptor document that formally defines the structure for the data.
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