The Design Procedures, and Successful Implementation Principles for Service Oriented Architecture - Coursework Example

Service Oriented Architecture Customer’s Name Customer’s Course Tutors Name March 14, 2011. Table of Contents Service Oriented Architecture 1 Table of Contents 2 Service Oriented Architecture 3 1.Introduction 3 2. Company information 3 2.1 Definitions 3 2.2 Company descriptions 4 2.3 Company specifications and integrations 5 3.Service oriented architecture approach to the problem 6 3.1Design 6 3.2Communication between the services 7 3.3 SOA design 8 3.4 Overview of the services offered by the companies 11 3.5 Web service elements 12 3.6 BPMN and BPEL 13 3.7 functions of the web service 14 4: Discussion: SOA allows companies to have flexible, interoperable systems and as a result the use of SOA facilitates the rapid change in business processes 15 4.1 Why SOA 15 4.2 SOA and Web Services 17 Benefits of using SOA 19 Bell, M. and Marks, E. (2006) Service-Oriented Architecture (SOA): A Planning and Implementation Guide for Business and Technology 21 22 Service Oriented Architecture 1. Introduction Service oriented architecture is lately being acclaimed as the new trend in most IT industries. This trend has a nature that gives the IT industry to harvest more from the investments at hand and also to offer new products and also services to faster markets in a way that is making the operational costs to go down to a great deal. This paper is a presentation of the design procedures, and successful implementation principles for SOA in three companies, A, B and C. In the context of this paper, the concept of service oriented architecture will be looked into and then dissected into the pros and cons that the architecture introduces to the IT world. 2. Company information 2.1 Definitions Service oriented architecture is an approach that is applied in information technology whereby applications are made to use the available services for instance the World Wide Web. In the implementation of the service oriented architecture, applications can be developed so as to use services or making some of the applications to be available as services so that they can be used by other applications. In this case, the services provide some specified functions such as business functions like credit analysis, making purchases, airline reservation and so on. In simple terms, it is generally a flexible and widespread method which ha been used to share business functions (Bell, 2010). WSDL stands for “Web Service Description Language”. This is an XML document that has the descriptions the interface of the web service. It contains the definitions of an XML schema that describes the web service. A WS-BPEL (Web Services Business Process Execution Language”) is a language that is based on XML which is used for the coordination of web services across one business process. It makes use of the WSDL in the description of the web services found in a process and also the interaction of the processes (Bell, 2010). 2.2 Company descriptions This paper is based on three companies which form part of a small supply chain that will hereby be utilized in this paper as the default supply chain. The chain includes the chain followed from the manufacturer to the supplier of bulbs. In this case, company A which will be known as Bulb1 is the manufacture of the bulbs, company B, Bulb2 is the main distributor of the bulbs and company C, Bulb3 is a supplier. This is a fully functional business supply chain which will require each part to be active. Company A, Bulb1 is the chief local manufacturer of bulbs. The business management systems in the system are made in X-Integrate software. X-Integrate which has been written in the .NET framework, helps businesses to be able to integrate the business systems and be able to consequently develop palpable service oriented architectures. This software has been designed in such a way that it can be able to create solutions which can aid in process communications in heterogeneous systems. This makes it simple for the business to engage in the service oriented architecture. Company B, Bulb3 is the second in the chain of command and also in the middle of the chain. This gives it a position of connecting the two other companies. Bulb3 is the chief distributor of the bulbs in the area. It gets its stocks directly from the manufacturer and distributes to other lesser companies which then make the supplies. The company relies on the orders that it receives from the suppliers and delivers according to their needs. It is always in contact with the manufacturer who produces the goods according to the demands of bulb2. Company C on the other hand is at the bottom of this supply chain. This company is the main local supplier of the bulbs in the retail market. It also sells the bulbs in wholesale to bigger markets. This company is in direct contact with bulb2 for the sake of replenishing its stock once it happens to go down. Company B, Bulb2, uses ADJ which has been written in J2EE whilst company C, bulb3 uses EntOrg1 which is built on the COMBINE platform. Looking at the platforms which the companies have created their business systems, it is possible for them to integrate despite their heterogeneous nature considering that they all support this factor. 2.3 Company specifications and integrations In this supply chain, the main objective is for bulbs to be distributed successfully from the manufacturer to the supplier via the distributer. In order for this chain to flow in a successful manner, it is essential that the three companies cooperate in their activities. Bulb1 has to be in a good and cordial relation with Bulb2 who also has to be in a good relationship with Bulb3. These relationships are mutually beneficial. At the bottom of the chain, we have Bulb3. On depleting or nearly depleting its stocks, this company sends an order to Bulb2. Bulb2 responds with sending bulbs to the company accompanied by an invoice. If the company notices a diminishing quantity of stocks in its stores, it sends an order to Bulb1 which does the same process. It fulfills this order by replenishing the bulbs and sending a consequent invoice. On receipt of the invoices, the involved company pays for the goods upon delivery or as per their mutual agreement. The companies have business systems which make the processes described above efficient, smooth and free of flaws. For Bulb3, once the stocks get to a certain level, orders are automatically generated which are automatically directed to bulb3. Bulb3 then engages in the order fulfillment process. The business systems in the companies have also been set in such a way that efficiency is guaranteed. In receipt of the order requests from bulb1, bulb2’s system generates the appropriate invoice and sends it to bulb1 together with the goods. When bulb1 makes the payments, the system generates the desired receipts and sends them to company C. this process of communication makes use of the web service and is repeated between company B and company A. 3. Service oriented architecture approach to the problem 3.1 Design In coming up with the integrated system which will be compliant with SOA, the design of the system has to be as per the setting of the services in the company relationships discussed as they give a setup of the criteria requirements. In the design of the SOA, the final piece should be a fully functional physical system which is then modeled from the requirements of the systems which are being integrated. A logical abstract representation can hence be modeled. The rules tat will be used in the supply chain are all taken into consideration in coming up with the business mode. 3.2 Communication between the services In setting up the interaction procedure between the different services, XML will be used to communicate. The protocol which is applied in this step is the “Simple Object Access Protocol (SOAP)”. SOAP assists in the provision of a common format for sending and receiving messages/information across an environment that is distributed. The use of the SOAP architecture assists in enhancing common means of exchange between the various clients and the services which are being used in the process. When this protocol is used in the supply chain under discussion, work is made simpler considering that the different systems are taken into consideration (Bell, and Marks, 2006). In this architecture, there has to be proper planning to ensure that the messages are properly controlled during transmission. This is made possible through the use of WSDL. In application of the WSDL, the various manners in which this XML schema has been designed allows the client to understand the format that was used to send the message and also the service together with the client is able to decipher the meaning behind a certain request. The manner in which this is done is quite straightforward; a business has registered its services, this registry has a pointer which is directed to a WSDL file contained in the WSDL document. When a different business in the chain searches for this service, it finds it in the registry. The design of the services tat are being implemented can thus be dissected into three distinct units which are the service, the message and WSDL. All these parts describe the design of the system in different parts of the message sending hierarchy. When the parts are being combined, the necessary abstraction procedures are put in place to ensure that the whole process is concealed from the people using the system. BPEL helps the system design procedure to arrange the business processes which are being integrated into an understandable mark up language. This assists in the integration of the web services to the outlined business processes. This can be viewed as the integration of the business processes to the web processes through the procedures and the formats that have been defined in the web services. 3.3 SOA design The main services that are being used by the three systems and are hence supposed to be integrated are the ordering service, invoicing service and lastly the delivery service. The necessary relationships between the services have erstwhile been discussed in this report. There are various strategies that can hence be applied so a to have the designs being put to an effective implementation. Some of the most effective approaches that can be applied in this procedure are the top down approach and the bottom up approach as will be seen in the following diagrammatic representations. The use of these strategies helps the designer in conceptualizing the procedures and thus be armed with enough knowledge to help him chose from the right approach. Top down approach A top down approach is generally one which starts with the highest detail of an idea downwards. A system is broken down into the sub systems which make it up. When designing a system using this approach, one first starts with the overview of the whole system and goes deeper, step by step, refining it up to when the whole system’s sub systems will have been defined to their bases. A top down representation of the strategies (Erl, 2008) Bottom up A bottom up approach is essentially one that seems to join up disintegrated parts of a system to a single piece. In this type of approach, the base elements or the subsystems are first defined. The process are then linked sequentially and with increasing levels until a top level system is achieved at the end of the day. The complexity of the system is visible at the end of the system. A bottom up approach to the design implementation (Erl, 2008) In the top down approach, there is an end result of a very good quality service. Reusability potentials and streamlines in the compositions are realized and increased through proper analysis. In the bottom approach, the services are in such a manner as to provide the services when they are needed. The modeling encapsulates logics so as to serve the requirements of the services which are at hand. The integration of the services for the three companies involved in this supply chain, the best approach which can be seen to fit in the process is the top down approach. This is basically due to such factors as reusability, efficiency and simplicity in break down of the individual systems. In general descriptions, the system is being develop in such a manner that the three companies keep in communication with the sub systems within them cooperating. Looking at these, this paper first takes a certain company, looks at its functions and dissects them. The same is done to the other two companies and the corresponding functions are grouped together. This brings out the idea of a top down design. 3.4 Overview of the services offered by the companies The services which will be provided by the system depend on the company specifications as will be hereby outlined. The main service requests include order request, order reception, order generation, checking of the stock, order delivery, invoicing, payments and issuance of receipts. These services are dependent on the company at hand. This means that there are services which are meant and belong to the manufacturer and some belong to the other companies and so on. This will be divided into modes which can be directly substituted into a mark up language. Bulb1 services: this company receives an order from bulb2 with “receive-order” service. Upon this, it produces the goods using “produce-goods” and then sends the goods to the company using “send-goods”. This company then receives payments using “receive-payment” Bulb2 services: this company receives orders from the supplier using “receive-order”. Upon this process, the systems checks for the availability of the ordered stocks using “check-stock”. If there is a stock deficit in the inventory, the systems generates an order request which is consequently sent to bulb1 using “send-order” request. Once bulb1 sends the goods to bulb2, bulb2 fulfills the requests of bulb1 by sending the goods through “send-bulb”. When there is an availability of the bulbs in the inventories of bulb2, they are sent to bulb1 upon request. When reception of the goods is confirmed, an invoice is sent to the supplier using “send-invoice”. This company pays the manufacturer using “send-payment” service. Once payment is made by the supplier, a receipt is sent through “send-receipt”. Bulb1 services: on ordering for the necessary goods, this company receives the bulbs from bulb2 using the “receive-bulb” service. The system for this company then processes the necessary payments for this company to bulb2 using “make-payment”. Once bulb2 receives the payment, they send a receipt and this is confirmed using “receive-receipt” service. The above diagram indicates a process of request and provision of services to by the various parts of the system. In the system that will encompass the service oriented architecture, there will be use of web services. These services are composed of a set of protocols and standards that are used fro communication, collaboration and information exchange with affirmed security, reliability, and interoperability. This paper will consider the three basic elements of the web services; service provision, service request and service registry. 3.5 Web service elements There are three basic elements which comprise a web service platform. The platform elements include SOAP, WSDL and UDDI. SOAP: this is an acronym for “Simple Object Access Protocol”. This is basically a communication protocol that has a format for sending of messages. SOAP’s mode of communication is through the internet and it is usually independent of the language and the platform being used. SOAP has its base on XML which makes it a very simple and also extensible element to use in the integration process. SOAP has a capability of circumventing firewalls. WSDL: this is a language that is based on XML used for the processes of location and description of web services. The term is an acronym for “Web Service Description Language”. The main functions of the standard are the location and descriptive functions. UDDI: this is an acronym for “Universal Description, Discovery and Integration”. This is basically a directory that is used to store the web services. This directory hosts all the web services that have been described in the WSDL. The basic mode of communication in WSDL is through SOAP. 3.6 BPMN and BPEL BPEL which stands for “Business Process Execution Language” is a platform which is adopted so as to make the business processes to be arranged into a mark up language like XML. When this phase of the integration is put in place, the process of sending of and receiving of messages is enhanced within the three chain companies and the use of web services to process these messages. There is an evident interaction between the business processes and the activities and services defined in WSDL. 3.7 functions of the web service 3.7.1: provision of services The web service has various characteristics that allow it to have the capabilities of providing the web services and thus make the integration possible. In the first place it is capable of receiving a message sent to it by another element that is requesting for the service through the use of SOAP. It then translates this message into a form that can be easily understood. The logics of the business which is then in process are put in place and encapsulated with the incoming SOAP message (Bell, 2008). This function is able to process the header blocks in SOAP and then retransforms the message into a form that can now be sent to the requestor in a manner that the requestor will understand. In this phase, there is an interface that is provided within the definitions of the WSDL which allows the requestor to be able to invoke requests. 3.7.2 Requesting services The first step in this process is the assembly of SOAP messages which will be used for the request in a manner that will comply to the definitions that are provided for in the WSDL. Some of the characteristics involved in this function are acceptance of service response from the service provider. On receiving this message, it combines the SOAP message to the business logic and the necessary steps in the business go ahead. This function has the ability of processing the SOAP header blocks in a message and interpretation of the WSDL definitions from the provider of the service. This part of the system is also responsible for transformation of the SOAP message to a manner which is comprehensible to the provider of the services (Bell, 2008). 3.7.3 Registry of services This is generally a list of the services which are available in the system by the providers; it allows the systems functions which need the services to query them from this source. This is the work of the UDDI. 4: Discussion: SOA allows companies to have flexible, interoperable systems and as a result the use of SOA facilitates the rapid change in business processes 4.1 Why SOA Software development practice has been through a lot of changes over time through changing models of programming and has thus led to quite a paradigm shift. The main factor behind this shift is the allowance for the various applications to be able to integrate through services, components or parts and on various platforms. One of the developments that are evident is the use of the Java programming language which is neutral of any platform. Additionally, XML has been able to provide data that is also platform, independent and self-descriptive. The use of web services has been seen to make applications interconnect and integrate in a manner that is independent of the object models. It has been evident that the use of XML messages allows java to invoke applications that can be based on DCOM, CORBA or even VB. The use of service oriented architecture (SOA) has had an effect of transformation from the object oriented architecture to the service oriented architecture. In this case, service components of an application are called during the invocation of a certain process as compared to the erstwhile objects. The application that is invoking a call thus is separated from running of the real transactions. Services are requested from any platform and the answers provided directly. This has made it possible to have systems running on IMS communicate to systems integrated in Domino servers and written in Lotus (Bell, 2008). There is a high likelihood that web services will be adopted as a more effective standard in the delivery of effective, reliable, scalable and also extensible interactions between machines due to the convergence of the required factors in a timely fashion courtesy of SOA. There is a likelihood that the emergence and the subsequent proliferation of SOA is bringing up a new age of infrastructure which is ubiquitous, open to all standards, cheap and thus more conducive to the adoption of the requisite web services as compared to what was offered by earlier systems like DCE or CORBA. There is going to be increased acceptance in the technological advancement in a universe which is now centered on networks so as to have interoperable business systems to met business objectives which conform to the current standards in the internet and also in the use of such technologies (Channabasavaiah et al, 2003). Advancement in technologies which make use of networks such as the TCP/IP protocol and also the use of related tools like UML and IDE, use of common platforms like .NET framework and the J2EE framework, use of common methodologies like object oriented and service oriented architectures have been known to provide the requisite infrastructure that has been able to give room for machine operations which are interoperable and coupled loosely which has had the advantage of better performance than before. This is one of the reasons as to why SOPA was chosen considering the interoperability flexibility that was offered by the use of platforms written in J2EE (EntOrg1) and .NET (X-Integrate). In addition to this, grid computing does not just involve applying large MIPS numbers with an aim of affecting the computing solution. It also allows for the dynamic location, relocation, balancing and management of the large numbers through the provision of a suitable framework. This ensures that the required applications are securely and readily available despite the system load. The effectiveness as well as availability of the various capabilities and new resources calls for the numerous applications that are available to be restructured.SOA is hereby made available during a period when there is a need for architecture to change to make use of the existing opportunities. It has effectively fitted in this era marked with the construction of changing solutions through e- commerce. 4.2 SOA and Web Services With the introduction of various web services, basic changes have occurred resulting into the execution of a real service oriented architecture. It is through this that the use of architecture can be examined in terms of its effectiveness in providing solutions for the identified general problems affecting a business. Looking at it in a business point of view, this entails the development of an application framework and architecture through which problems affecting a particular business can be identified and relevant solutions obtained and consistently and effectively implemented. It is important to however note that service oriented architecture differs from web services in such a way that web services entails the collection of different technologies such as SOAP, XML, UDDI and WSDL. This allows for the identification and implementation of relevant programming solutions to address different but specific application integration as well as messaging problems. The application of these technologies is however approaching maturity and will with time get replaced with more effective and better ones. These technologies will not therefore need to act as a basis for the implementation of SOA. SOA is on the other hand an architecture which is completely independent of any kind of technologies (Gottschalk, 2009). SOA contrary to web services rises above the various technologies. In the context the business environment, SOA can be defined as an architecture application whereby every function is defined as an independent service containing clearly defined interfaces which can be sequentially be used to create business processes. Each function is in this case defined as a service, business function and a business transaction containing functions of a lower level as well as functions related to system service. Such services operate independently as external components whose main aim is to produce the required results regardless of the process they use to do this. This basically means that the interfaces can be described as those within the architectural level irrespective of whether this occurs within or outside the system(local or remote), the interconnect protocol or scheme to create the invocation or the various infrastructure components’ needed for the connections. The service can be in such a way that it is done within one application or in an asymmetric- multiprocessor with differing address spaces on a system that is totally different within a given corporate –intranet or even within an associate’s system application used within a B2B-configuration.interfaces mainly lays its emphasis on this application (Gottschalk, 2003). It is capable of defining the parameters that are required and the results too thus defining the nature of the service and the technology involved in the implementation. The process allows for realization of two critical processes; the manageable services and the services which are independent. The process of managing this services is inclusive of various issues as discussed hereby; security (for request authorization, encryption, decryption and validation), dynamic rerouting (for fail over and load balancing), maintenance (for management new service versions). Benefits of using SOA The application of SOA can contribute to the creation of flexible, agile and open environments that has enabled interoperability and a combined autonomy. The use of SOA happens to fulfill most of the needs and changes in a variety of ways and means. a) Integration: it is possible to combine services with other services and come up with higher level services in dynamic or static forms. b) Due to abstraction in service interface and implementation, it is possible to have services work on heterogeneous platforms of hardware and software. This ascertains the possibility of mixing equipments used for automation from a variety of vendors. c) There is an increase in flexibility, adaptability to change and agility due to the ability to reconfigure or/and replace services, deployment of services is possible in an incremental pace over a period of time. Entities which are communicating can be able to exchange resources and also be able to work in unison through peer to peer communication and direct communication. This is a method that can be used to enhance the rate of responsiveness, configurability and efficiency (Zimmerli, 2009). d) There is reduction in the cost of developing systems as services are reused and high level application programming is applied. e) Scalability is assured considering that the different services have their unique complexities. This also enhances maintainability and manageability as the devices have a high level interface for management due to facilitation of configuration, diagnosis of faults and monitoring. f) The use of a collection of systems to come up with a single system brings forth a system which is fault tolerant (Peltz, 2003). References Bell, M. (2008). "Introduction to Service-Oriented Modeling" Service-Oriented Modeling: Service Analysis, Design, and Architecture. Wiley & Sons. Bell, M. (2010) SOA Modeling Patterns for Service-Oriented Discovery and Analysis. Wiley & Sons Bell, M. and Marks, E. (2006) Service-Oriented Architecture (SOA): A Planning and Implementation Guide for Business and Technology Channabasavaiah K., Holley K. & Tuggle E, (2003). Migrating to a service-oriented architecture. (IBMDeveloperWorks). Retrieved March 26, 2008, from http://www- 128.ibm.com/developerworks/library/ws-migratesoa/ Erl, T. (2007) Soa: principles of service design, Press Upper Saddle River, NJ: Prentice Hall. Gottschalk, K. and the IBM Web Services Architecture team, (2009) “Web Services architecture: Overview - The next stage of evolution for e-business” http://www.ibm.com/developerworks/webservices/library/w-ovr/ Jammes, F. and Smit, H. (2005), Service-Oriented Paradigms in Industrial Automation, IEEE Transactions on Industrial Informatics, Vol.1 (1): 62-70. Peltz, C. (2003) “Web Services Orchestration and Choreography”, IEEE Computer, Vol.36 (10): 46-52. service-oriented architecture” IBM DeveloperWorks. Shen, W. and Norrie, D. (1999) “Agent-Based Systems for Intelligent Manufacturing: a State-of- the-Art Survey”, International Journal on Knowledge and Information Systems, Vol.1 (2):129-156, 1999. Zimmerli, B. (2009) Business Benefits of SOA, University of Applied Science of Northwestern Switzerland, School of Business. Read More