IT infrastructure comprises of multiple targets that interact with each other to provide numerous business functions. These business functions are used by both internal and external consumers. It is apparent that no IT management solution is complete without a functional view of the business services provided by the infrastructure. Such a functional paradigm of the IT topology with a business-centric focus is known as the service model.
Continuing with the travel portal example, the portal provides a wide gamut of business services to different consumers such as flight reservation, hotel reservation, and so on. In addition the portal also consumes services from other service providers to enhance their business functions. For instance, the travel portal may rely on a third-party payment gateway to facilitate all payment-related operations. With the service modeling, each of these business services is represented as a different entity having its own respective business value.
The following image indicates the various business services provided by the Travel Portal Application. The travel portal provides a suite of business functions such as flight search, hotel search, car rentals, reservations, and so on. In addition, the travel portal also consumes the payment service from the service partner illustrated as follows:
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Service modeling allows the administrators to manage the infrastructure viewed through a business service dimension. This is different from the traditional management philosophy that relies on a bottoms-up approach in managing and maintaining individual components. Defining a service model and applying that in operations management helps the administrators map the business priorities in their day-to-day management tasks. This is an optimization over administrators working with individual components in silos, clueless about their impact on overall business strategy. This is a significant leap in bridging the gap between IT and business management.
Service modeling is a top-down approach in managing the IT infrastructure. At the end of the day, the business service offered by a data center is the very reason for its existence. This essence is extremely significant to IT infrastructure in moving up the value chain in the larger organizational goals. This is a paradigm shift in focus from managing individual components to managing the business service itself as an entity. While this brings in its own set of challenges in modeling and monitoring the underlying infrastructure, it drives all decision-making processes from a service consumer perspective. The service model provides that vital missing link between IT admin and the end user.
For example, in the absence of a business service-centric mindset, a database administrator travel portal would have applied a database patch-set and perform restart operation without knowing the business impact. There might be qualitative assurances such as SLAs in place with partners based on the up time. With the business service model in place, the impact of any operation on the service level is assessed prior to the execution of any IT operation. The administrator now can determine the current service level of the business function and then check for possible violations in assurances before embarking on significant operations. This requires working with the business teams to determine the right maintenance window before any critical configuration change.
These days where distributed technology such as cloud computing, grid computing, managed and hosted services, and on demand services are prevalent, there needs to be an assurance on the quality of the service that is offered. This assurance is represented as Service-Level Agreements or SLAs. The SLAs between the service consumer and the provider may be arrived based on various parameters. The key parameters determining the service levels include:
Availability: Assurance on the up time of the business service. As an example, the travel portal may be required to be available 99 percent of all business hours.
Performance: Assurance on the quality of performance of the business service. For example, payment transactions would be completed within three seconds.
Usage: Assurance on the scalability and robustness of the service. For instance, the travel portal may support up to 100,000 requests per second.
Support: Assurance on maintenance and support whenever there is a service disruption. For example, any P1 support ticket will be closed in eight hours.
Service modeling also helps in tracking the service levels of dependent service providers. As discussed above, the travel portal is dependent on the third-party payment gateway for the payment-related functional flows. If there is any drop in service quality levels from the agreed levels, this might impact the business process flows of the travel portal. This drop ultimately impacts the end users of the
travel portal, which could potentially result in loss of business revenue. With the service model, both service providers and consumers can track potential service-level disruptions.
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The various business service offerings within a business enterprise comprise of multiple technologies and hardware. The service model enables the management of the business functions and their service levels without getting overwhelmed by the variety and scale of the underlying technology. For example, the travel portal provides the ability to perform search on both domestic and international flights by interacting with various partner airline web services and exposes this flight search as a web service. This business function is made possible through complex interactions between hundreds of components spread across multiple data centers and locations. These different components leverage on different technologies of hardware and software. The travel portal has an agreement with its business partners to provide the flightsearch function within a three-second period. In the absence of the service model, it becomes extremely cumbersome to define and monitor the performance of this business function. The sheer magnitude of the technologies involved as well as the scale and range of the IT components involved would require specialized skill sets and domain knowledge, to manage such a distributed infrastructure. By visualizing the flight search using the service model, the IT management of the flight search is simplified and tracking of the service level becomes straightforward. The service model hence provides an abstraction to get past the complexity of the IT implementation and focus on the key business goals.
The system and group models, as discussed before, provide the mapping between business goals and the IT infrastructure within the enterprise. Both the system and group models aid in getting a unified view of the various technologies within the topology into a single entity. In a modern day enterprise, it is common to share the same IT infrastructure supporting multiple business functions for effective utilization of resources. For example, in the travel portal, the same application server and database may host both hotel search and flight search applications. The system or group targets associate the application servers and databases into a single entity;
the multiple business functions offered by such an entity will still be required to be distinguished. For instance, the service-level assurance for a hotel search may be different from the service levels offered by the flight search. So the hotel search and flight search business services would need to be modeled as two different entities having different service-levels. The service models help in visualizing and monitoring different business services offered within the same IT infrastructure.
The business services provided by an enterprise IT infrastructure can be visualized in two different paradigms. Each of these services can be envisaged as an end result of the associated IT components in the data center that interact with each other. The business services can also be represented based on an external view of the business services. These service models are complementary in nature and provide different perspectives of the same business service.