Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Service Oriented Architecture Ruwan Wijesinghe

2 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL What is SOA ? A loosely-coupled architecture designed to meet the business needs of the organization SOA is a standards-based design approach to creating an integrated IT infrastructure capable of rapidly responding to changing business needs. SOA provides the principles and guidance to transform a company’s existing array of heterogeneous, distributed, complex and inflexible IT resources into integrated, simplified and highly flexible resources that can be changed and composed to more directly support business goals.

3 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL What is Service Schema Message formats (what are the data to be included on each message type and how they should be organized) Contract Set of operations supported by the service and input and output messages for each operations E.g. Operation – AddEmployee – Input Message – Employee Information – Output Message – Success or failure of the operation Policy Operational details, like communication protocol, security, auditing, etc.

4 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Implementation of SOA

5 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Implementation of SOA Expose Expose existing computing capabilities as services These capabilities might be currently available in difference heterogeneous applications New business capabilities can be developed if required Compose Compose these services to construct business process and expose them as services This supports agile, loosely coupled business process Workflow engines can be used to implement these services Consume Develop UI applications for the users to interact with these business processes services

6 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Service Aggregation Services can have different levels of granularity in offerings. Fine grain services can be aggregated to provide coarser grained services.

7 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Extending Classic Architectures with Services Business Workflows Business Capabilities User Interfaces

8 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Business Values SOA enables businesses to develop a new generation of dynamic applications that address a number of top- level business concerns that are central to growth and competitiveness. SOA solutions promote: Stronger connections with customers and suppliers. Enhanced business decision making Greater employee productivity

9 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Stronger Connections with Customers and Suppliers. Expose business services to customers and supplies By making available dynamic applications and business services to external customers and suppliers, not only is richer collaboration possible, but customer and partner satisfaction is increased. Expose business process as service SOA unlocks critical supply and demand chain processes such as outsourcing of specific business tasks from the constraints of underlying IT architectures, thereby enabling better alignment of processes with organizational strategy.

10 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Enhanced Business Decision Making By aggregating access to business services and information into a set of dynamic and composite business applications Decision makers gain More accurate and comprehensive information Flexibility to access that information in different forms of presentation (Web, rich client, mobile device) that meets their needs.

11 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Greater Employee Productivity By providing Streamlined access to systems and information Enabling business process improvement businesses can drive greater employee productivity. Employees can focus their energies on addressing the Important, value-added processes On collaborative, semi-structured activities rather than having to conform to the limitations and restrictions of the underlying IT systems.

12 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL SOA Scenarios Some key scenarios where SOA shows a greater Information Integration Legacy Integration Process Governance Consistent Access Resource Virtualization Process Externalization

13 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Information Integration The complete description of a customer might be spread across a dozen business applications and databases. Information integration services are an effective means for both Presenting your application portfolio with a unified view of these key entities Ensuring the consistency of the information across all of your back-end systems This supports to have a “ single view of the customer problem ”

14 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Legacy Integration The Legacy Integration scenario focuses on the tactical use of services to preserve existing investments in business applications, while extending the functionality of the capabilities upon which they deliver. For example, a service might add support to comply with new regulations in front of an existing ERP package

15 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Process Governance In a Process Governance scenario, “message headers” are used to communicate key business metadata; from the turnaround time on customer requests to the identity of the approvers for specific business decisions. This metadata is captured by a utility service (as discussed previously), for real-time and/or aggregated analysis. "

16 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Consistent Access This scenario enables a services layer to ensure consistent enforcement of a variety of operational requirements when a diverse set of applications needs to connect to a critical back-end resource. By mandating that all access be routed through a service facade, an organization might enforce consistent access authorization, cost distribution and load management.

17 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Resource Virtualization A Resource Virtualization scenario can be utilized to help enforce loose coupling between resources and consumers, effectively insulating consumers from the implementation details of the targeted resources. Typical examples of Resource Virtualization may include: Context-sensitive and content-sensitive routing of requests, such as sending a real-estate inquiry to the agent in the specified geography who specializes in farm properties. Routing of requests to partitioned information stores (without requiring the requestor to understand partitioning schemes). Load balancing requests across available resources; from customer service representatives to streaming video feeds.

18 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Process Externalization Process Externalization scenarios utilize Web services to securely expose business services to outside partners. For example Cell phone service providers and Internet portals frequently use web services to aggregate content Customer-facing organizations may use services to build composite offers (such as travel packages that include airfare and rental cars).

19 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Enterprise Service Bus The term Enterprise Service Bus (ESB) is a family of products used in implementing the messaging capabilities of a service oriented infrastructure. The messaging capabilities required in a service oriented infrastructure extend the functions of traditional Enterprise Application Integration (EAI) Message Oriented Middleware (MOM) Support for Web Service standards Integration with other service infrastructure components such as policy management metadata registry operational and business monitoring frameworks

20 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL How can your organization get started with SOA? Make sure that you have sound business drivers Top-down approaches do not work in the real world. Bottom-up approaches are not manageable either. In contrast, organizations that are successful with SOA often adopt a middle-out approach. Demonstrate value in rapid iterations. Time-to-value is a critical, healthy metric (The “trust-me” approach is not a healthy model for successfully leveraging SOA).

21 Copyright ©2004 Virtusa Corporation | CONFIDENTIAL Reference Service Oriented Architecture (SOA) in the Real World - Microsoft Cooperation