Enterprise Architecture has become a rising area of interest for many professionals in order to manage the technology portfolio of an enterprise. TOGAF (The Open Group Architecture Framework) provides methods, models and references to guide the design, implementation and evolution of business capability by means of IT functionality. ITIL (Information Technology Infrastructure Library) makes a similar promise from a different perspective and has been the favourite reference for many IT service / solution provider organizations with its unique focus to the IT service lifecycle. I tried to reveal the unique characteristics, approaches, differences and highlights of these frameworks in order to assist the readers to understand the use of these frameworks, and guide the potential efforts for adaptation of any or both of the frameworks in the enterprise environment.
TOGAF provides a well-defined process for the analysis, design and implementation of strategy. The Architecture Development Method (ADM) facilitates the journey from the baseline to the target state for the business, information systems, and technology architectures consecutively. This method is mostly useful when conducting a project to define the change of an IT system (new, replaced or transitioned) in response to desired business outcomes / capabilities. The developed work products define the desired functionality and stored as building blocks within the Architecture Repository. This model provides consistency and controls complexity for transformation projects by facilitating the selection of applicable standards, technologies and products across the enterprise. Redundant efforts to design a system are also likely to be eliminated by reuse of applicable architecture components.
ITIL’s perspective is the definition of good practice (can be mapped to the target state in TOGAF) without providing direct guidance for the journey to that. Although ITIL Continual Service improvement provides limited guidance (compared to TOGAF) to support the transformation activities, the focus is not at the enterprise level but rather based on the existing IT services and their fitness to business needs. Nevertheless, the ITIL service life cycle domains cover a large set of principles, processes and activities that address capabilities having direct impact on service provider’s performance. For this reason, ITIL has become a unique guidance for IT service organizations.
TOGAF does not cover the processes and activities for operational management but refers to other frameworks, such as ITIL. As these operational processes and activities assist to develop architectural assets, practitioners may benefit from the ITIL guidance to form the desired capabilities and use TOGAF as the framework for the transformation to achieve these capabilities.
Implementation support (Transition Planning) is provided within TOGAF ADM during the transformation, linking the architecture project with portfolio / project and operations management frameworks. Compliance of implementation projects to the architecture is controlled via the Implementation Governance process. Continual iteration of architecture development (partially or complete) ensures the evolution of architecture due to the changes of circumstances such as new business initiatives, technology enhancements or limitations.
Another important aspect of TOGAF is the definition of viewpoints to present and communicate the architecture to various stakeholders as they may have varying priorities, interests and concerns. Viewpoints define the required work products (catalogues, matrices, diagrams, etc) to be produced from business to technology, address all pertinent concerns from high-level overview to lower-level detail and continually refer back to the concerns and requirements of the stakeholders throughout the process to ensure the integrity and fitness of the architecture. ITIL does not explicitly define viewpoints but addresses relevant concerns within its 5 domains of the service life cycle; service strategy, design, transition, operation, and continual improvement. Each domain links to the other with specific inputs & outputs developed as per guidance. For example, Service Design produces solution designs, architectures and standards that are to be consumed during the service transition phase. TOGAF can provide the framework to classify and store all these deliverables in a consistent and integrated manner to facilitate their management throughout their life cycle.
In summary, TOGAF has matured to an enterprise architecture framework inspired from the detailed plan of the system and its components that forms the enterprise. ITIL provides the good practice, including the principles, processes and activities for successful delivery of an IT service and TOGAF can be used as an underlying platform to deploy ITIL guidance within a transformation project. I also looked into this approach further within a former article; Unifying IT Best Practice Frameworks and Standards within TOGAF. As both frameworks have unique characteristics and approaches, a direct comparison will likely mislead readers. Nevertheless, I consolidated the below table to highlight the major attributes of each in order to summarize the touch points within this article.
Highlights of TOGAF and ITIL
|Inspired from the detailed plan of the system and its components that forms the enterprise.||Inspired from the excellence of IT services to deliver business value.|
|Strong focus for the journey towards the target state.||Strong focus to define the target state.|
|Strong guidance to address business requirements with IT solutions (can be adapted by any enterprise leveraging IT to run its business)||Strong guidance for operational excellence of IT services (the obvious reason of preference by IT service provider organizations.|
|Defines various viewpoints to represent interests and concerns of relevant stakeholders.||Groups guidance in 5 domains as per service life cycle (service strategy, design, transition, operation and continual improvement).|