This chapter looks at establishing procedures for managing change to the new architecture.

Objective

The objective of Phase H is to establish an architecture change management process for the new enterprise architecture baseline that is achieved with completion of Phase G. This process will typically provide for the continual monitoring of such things as new developments in technology and changes in the business environment, and for determining whether to formally initiate a new architecture evolution cycle.

Phase H also provides for changes to the framework and principles set up in the Preliminary Phase.

Approach

The goal of an architecture change management process is to ensure that changes to the architecture are managed in a cohesive and architected way, and to establish and support the implemented enterprise architecture as a dynamic architecture; that is, one having the flexibility to evolve rapidly in response to changes in the technology and business environment.

The change management process once established will determine:

• The circumstances under which the enterprise architecture, or parts of it, will be permitted to change after implementation, and the process by which that will happen
• The circumstances under which the enterprise architecture development cycle will be initiated again to develop a new architecture

The architecture change management process is very closely related to the architecture governance processes of the enterprise, and to the management of the Architecture Contract (see Architecture Contracts) between the architecture function and the business users of the enterprise.

In Phase H it is critical that the governance body establish criteria to judge whether a change request warrants just an architecture update or whether it warrants starting a new cycle of the Architecture Development Method (ADM). It is especially important to avoid "creeping elegance", and the governance body must continue to look for changes that relate directly to business value.

Guidelines for establishing these criteria are difficult to prescribe, as many companies accept risk differently, but as the ADM is exercised, the maturity level of the governance body will improve, and criteria will become clear for specific needs.

The Drivers for Change

There are many technology-related drivers for architecture change requests. For example:

• New technology reports
• Asset management cost reductions
• Technology withdrawal
• Standards initiatives

This type of change request is normally manageable primarily through an enterprise's change management and architecture governance processes.

In addition there are business drivers for architecture change, including:

• Business-as-usual developments
• Business exceptions
• Business innovations
• Business technology innovations
• Strategic change

This type of change request often results in a complete re-development of the architecture, or at least in an iteration of a part of the architecture development cycle, as explained below.

The Change Management Process

The change management process needs to determine how changes are to be managed, what techniques are to be applied, and what methodologies used. The process also needs a filtering function that determines which phases of the architecture development process are impacted by requirements. For example, changes that affect only migration may be of no interest in the architecture development phases.

There are many valid approaches to change management, and various management techniques and methodologies that can be used to manage change; for example, project management methods such as PRINCE 2, service management methods such as ITIL, management consultancy methods such as Catalyst, and many others. An enterprise that already has a change mangement management process in place in a field other than architecture (for example, in systems development or project management) may well be able to adapt it for use in relation to architecture.

The following describes an approach to change management, aimed particularly at the support of a dynamic enterprise architecture, which may be considered for use if no similar process currently exists.

The approach is based on classifying required architectural changes into one of three categories:

1. Simplification change : A simplification change can normally be handled via change management techniques.
2. Incremental change : An incremental change may be capable of being handled via change management techniques, or it may require partial re-architecting, depending on the nature of the change. See Guidelines for Maintenance versus Architecture Redesign for guidelines.
3. Re-architecting change : A re-architecting change requires putting the whole architecture through the architecture development cycle again.

Another way of looking at these three choices is to say that a simplification change to an architecture is often driven by a requirement to reduce investment; an incremental change, by a requirement to derive additional value from existing investment; and a re-architecting change, by a requirement to increase investment in order to create new value for exploitation.

To determine whether a change is simplification, incremental, or re-architecting, the following activities are undertaken:

1. Registration of all events that may impact the architecture
2. Resource allocation and management for architecture tasks
3. The process or role responsible for architecture resources has to make assessment of what should be done
4. Evaluation of impacts

Guidelines for Maintenance versus Architecture Redesign

A good rule-of-thumb is:

• If the change impacts two stakeholders or more, then it is likely to require an architecture re-design and re-entry to the ADM.
• If the change impacts only one stakeholder, then it is more likely to be a candidate for change management.
• If the change can be allowed under a dispensation, then it is more likely to ba be a candidate for change management.

For example:

• If the impact is significant for the business strategy, then there may be a need to redo the whole enterprise architecture - thus a re-architecting approach.
• If a new technology or standards emerge, then there may be a need to refresh the Technology Architecture, but not the whole enterprise architecture - thus an incremental change.
• If the change is at an infrastructure level - for example, ten systems reduced or changed to one system - this may not change the architecture above the physical layer, but it will change the baseline description Baseline Description of the Technology Architecture. This would be a simplification change handled via change management techniques.

In particular, a refreshment cycle (partial or complete re-architecting) may be required if:

• The Foundation Architecture needs to re-aligned with the business strategy.
• Substantial change is required to components and guidelines for use in deployment of the architecture.
• Significant standards used in the product architecture are changed which have significant end-user impact; e.g., regulatory changes.

If there is a need for a refreshment cycle, then a new Request for Architecture Work must be issued (to move to another cycle).

Inputs

Inputs to Phase H are:

• Request for Architecture Change - technology changes:
  • New technology reports (New Technology Reports)
  • Asset management cost reduction initiatives
  • Technology withdrawal reports
  • Standards initiatives
• Request for Architecture Change - business changes:
  • Business developments
  • Business exceptions
  • Business innovations
  • Business technology innovations
  • Strategic change developments

Steps

Key steps in Phase H include:

Outputs

The outputs of Phase H are:

• Architecture updates
• Changes to architecture framework and principles
• New Request for Architecture Work (Request for Architecture Work), to move to another cycle

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