The modeling techniques that are covered in the previous sections are derived from industry standard guidelines. Information Technology Infrastructure Library or ITIL is one of the prominent standards that provides a set of guidelines around Enterprise IT Management. It looks at all aspects of the IT management ecosystem including business services management, IT operations management, and its development. ITIL has evolved from v1 to v3, which is the current form. Before the evolution of the ITIL guidelines enterprises, the world didn't have an accepted set of frameworks, tools, and policies for IT management. This forced each enterprise to develop its own set of frameworks for managing the complexities in the data center. However, this made the landscape very complex for private external management vendors to develop standard products that could potentially take advantage of common guidelines for IT management. Essentially this drove the cost of managing IT upwards. This ensured that enterprises and governmental agencies came together to define a common set of guidelines for suggested frameworks around IT management. The results of this initial attempt of consolidation of IT management principles and guidelines were released as ITIL v1.
As can be imagined, the initial versions of the guidelines were an attempt to consolidate the best practices of IT management from different governmental and private enterprises. This attempt at consolidation was not very successful, and the guidelines grew very large and ran into many volumes. ITIL v2 was the next attempt at consolidation of the guideline sets from v1. However, this time the focus was more towards managing the IT infrastructure through a services-based model. This focus on business services modelling and management ensured a wider acceptance and understanding of the guidelines. This acceptance and understanding led to a further consolidation of the guidelines with a renewed focus on business services lifecycle management, and the guidelines were released in 2007 as v3 which is the most recent form.
As seen from the evolution of ITIL guidelines above, post the initial consolidation of IT management principles, the focus has shifted from a process-based management of the infrastructure to a services-based model and its management. This focus has remained largely intact, and has also gained acceptance in almost all the large enterprises as the guidelines for IT infrastructure modeling, management, and its overall governance.
The latest specifications, that is, ITILv3 (http://www.itil-officialsite.com/) focus on service lifecycle management. The lifecycle of services management is described in the following five steps:
1. Service strategy: This step is the most important step and acts as the basis of the entire lifecycle. This deals with the requirements for a business service and the policies that govern its implementation and delivery.
2. Service design: This step follows the strategy and deals with the design of the business service. This defines the guidelines for selection of technology, design architectures, and all other design aspects that enable the final service to deliver on the agreed set of requirements.
3. Service transition: This step follows the design and implementation of the services and focuses on the actual delivery of the service to the end customers. This step primarily deals with service evaluation as against the defined requirements and management aspects such as configuration management, release management, and change management.
4. Service operation: This step follows the transition and deals with the continuous operations of the service. This focuses primarily on event, incident, and problem management as well as deals with access management.
5. Continuous service improvement: This is the final step in the lifecycle of the business service and as the name suggests, deals with processes that can help improve the current form of the service. This step deals with managing and reporting the service-levels. These reports are then analyzed to identify potential areas of improvement. These recommendations are fed back to the operations teams to optimize infrastructure usage to ultimately achieve high service-levels. As suggested by the name, this is a continuous process and attempts to maximize the efficiency of service delivery to the end customers.
The lifecycle described above is a step process where each step is a logical continuation of the preceding steps. The final steps of the lifecycle then feed back into the first step. This feedback is critical in gathering the requirements for the next version of the service and also for its subsequent design and implementation.
This section has attempted to provide an overview of the evolution of the ITIL guidelines with a focus on its current form (v3). As one can imagine these guidelines are very comprehensive in nature, with each step requiring a very detailed description and discussion. However, as seen above, the focus is clearly on managing the IT infrastructure as a tool that delivers the business service. This focus is now widely accepted and adopted as the strategy of choice for IT management by almost all CTOs.