Introduction
Since the development of the first computer, the technology has consistently been characterized by constant advancement. The different laws have described this; with the Bell’s Law anticipating a new technology every ten years and the Moore's laws stating that the number of transistors per chip will always double every 24 months. The advancement has resulted into pervasive computing making computing a part of everyday life.
Distributed computing is a branch of computing, where computing points of execution are located across-networked computing. this approach offers several advantages including resource sharing, reduced cost to performance ratios, portability of the software, increases the scalability of the organizational set up without having the exhaust the available computing resources, through replication the approach provides for fault tolerance and increased computing capacity.
Distributed technology dates back in the 1960's when the first message passing operating system architecture was studied. However, it was not between computers but could only be implemented by processes on the same machine. A truly distributed system was implemented on a local area network in 1970's following the establishment of the ARPANET by the United States military. Developments of ARPANET lead to the introduction of Internet with the email program being the most successful application to be implemented.
Internet technologies continued to advance at a very first rate. In early 1980 the hypertext language was developed to provide a common communication language. The acted as the precursor to the development of World Wide Web, which was the turning point for data sharing among the scientist all over the world. It was characterized by the development of the hypertext transfer protocol (HTTP), the first web browser (world-wide-web), the first HTTP server software, the Hypertext Markup Language (HTML), the first web server and the first web pages. That marked the first limb toward distributed computing technologies.
Early web browsers marked the significant advancement in distributed technologies. Different software development companies added different abilities in their browser leading integration of multimedia features. The web browser embedded graphics, scripting, and animation which boosted adoption of the web usage in the different area. Establishment of the World Wide Web Consortium ensures standardization of the web technologies improving the quality of web.
Improved web quality led to increased web demand among the business community with the opportunity to get free advertisements and instant world-wide information. This resulted to the web-based commerce and instant communication which pioneered the dot-com bubble which marks the need for better technologies.
Availability of new technologies and demand for better web services lead to the establishment of the Web 2.0. Web 2.0 is defined by emphasizing on user generated content, usability and interoperability. Technologies such as Ajax, Dojo Toolkit, jQuery, JavaScript Mool tool and many others allowed interactivity and communication. The demand for synchronized data communication and formatting lead to the development XML and the JavaScript object on motion (JSON) technologies.
The XML was developed in 1996 by Jon of the Sun Microsystems. The technology defined rules for encoding documents in a format that is both legible to human and machine. The design provided simplicity, generality and usability across the Internet. Different companies have heavily adopted the XML technology. Using the XML syntax different companies have developed their version including RSS, Atom, SOAP, and XHTML. Microsoft Office has also incorporated XML formats in most of its tools [1].
The syntax for XML has also been improved over time. Different versions of XML have been enhanced to include new features. With constant improvement the XML has become an essential component in all aspects of the web.
Service – oriented architecture has also been a key concept in web advancement. The architecture provides the ability to integrate business process data and organizational knowledge. This architecture allows for different application to provide service to each other over the network. This principle is always independent of any vendor, product or technology making service across the web less complex. This service though is built on similar principles as the web services the architecture is all about designing of the web environment.
The service oriented architectures are used together with the Simple Object Access Protocol(SOAP).which is mainly a protocol specification that is used to exchange structured information in the implementation of the web services
The design for the service oriented architecture is organized in different levels including structured communication, middleware, and ad hoc network programming. The ad hoc level targets communication technologies mainly the interprocess communication mechanisms such as pipes, shared memory, and the sockets. The mechanisms have been advanced over a period of time. The ad hoc level targets to conceal the application used in the distributed complexities of communication between the different computers over the network.
The next level, the middleware provide dedicated services to the communicating processes. In this level, there has been continuous advancement over a period of time. A major advancement was marked by the development of distributed object computing middleware in the early 1990s. This technology leverages the object-oriented techniques to distribute the reusable services and applications in an efficient, robust and flexible manner over different computing and networking elements. The Java RMI and the COBRA are some of the distributed object computing middleware that provides the interface between the server side and client side.
The SOA also provides the server runtime environment for different services such as transaction access, replication, security and load balancing. Through the use of the XML, the different components that have their associated metadata can easily communicate. To achieve the new demand for synchronous communication alternative approaches have been developed by different companies. Message-oriented middleware is one of the new methods adopted especially by the IBM MQ series and the TIBCO Rendezvous [2]. This middleware allows the sender to transmit data to the receiver without blocking other processes that in execution.
All these concepts being adopted in the service oriented architectures are meant to fix the different broken architectures and bring agility to the web users. The SOA utilization of services diversities has addressed the challenge of different environments of execution with providers of adequate infrastructure rather than developing custom made solution.
Conclusion
Advancement in service-oriented architecture have continued to enjoy a lot of success, the current adoption of cloud computing is a good example of the major achievements of SOA. The advancements are made possible by the availability of the SOA platform that will support all the required runtime. Technologies such as WSDL and UDDI are also contributors to the advancement of the SOA by providing web service and maintaining the registry respectively. Although the improvement has been made in distributed computing more still needs to be done to achieve the desired features of an idea network
References
[1]M. Gashti, "Investigating Soap and Xml Technologies in Web Service", IJSC, vol. 3, no. 4, pp. 15-19, 2012.
[2]M. Mohammadi and M. Mukhtar, "A Review of SOA Modeling Approaches for Enterprise Information Systems", Procedia Technology, vol. 11, pp. 794-800, 2013.
