"The first key characteristic of the emergent approach is best summarised as 'architect the lines, not the boxes', which means managing the connections between different parts of the business rather than the actual parts of the business themselves," said Bruce Robertson, research vice president at Gartner. "The second key characteristic is that it models all relationships as interactions via some set of interfaces, which can be completely informal and manual - for example, sending handwritten invitations to a party via postal letters - to highly formal and automated, such as credit-card transactions across the Visa network."
Gartner has identified seven properties that differentiate emergent architecture from the traditional approach to EA:
1. Non-deterministic - In the past, enterprise architects applied centralised decision-making to design outcomes. Using emergent architecture, they instead must decentralise decision-making to enable innovation.
2. Autonomous actors - Enterprise architects can no longer control all aspects of architecture as they once did. They must now recognise the broader business ecosystem and devolve control to constituents.
3. Rule-bound actors - Where in the past enterprise architects provided detailed design specifications for all aspects of the EA, they must now define a minimal set of rules and enable choice.
4. Goal-oriented actors - Previously, the only goals that mattered were the corporate goals but this has now shifted to each constituent acting in their own best interests.
5. Local Influences: Actors are influenced by local interactions and limited information. Feedback within their sphere of communication alters the behaviour of individuals. No individual actor has data about all of an emergent system. EA must increasingly coordinate.
6. Dynamic or Adaptive Systems: The system (the individual actors as well as the environment) changes over time. EA must design emergent systems sense and respond to changes in their environment.
7. Resource-Constrained Environment: An environment of abundance does not enable emergence; rather, the scarcity of resources drives emergence.
Gartner said that enterprise architects must be ready to embrace the inversion of control. Where in the past, they controlled all EA decision making, they must now accept that that business units demand more autonomy. For example, they must understand that employees demand that they can use their personal devices, there is increased integration with partners and suppliers, customers demand access to information using the technology of their choice, and regulators require more information.
"The traditional top-down style worked well when applied to complex, fixed functions - that is, human artefacts, such as aircraft, ships, buildings, computers and even EA software," said Mr Robertson. "However, it works poorly when applied to an equally wide variety of domains because they do not behave in a predictable way. The traditional approach ends up constraining the ability of an emergent domain to change because it is never possible to predict - and architect for - all the possible avenues of evolution."
Gartner analysts will further explore this new enterprise architecture approach at the Gartner Enterprise Architecture Summit 2009, taking place at the Royal Lancaster hotel, London, on 14-15 September. Over two days, the Summit gathers ten leading Gartner analysts who will help delegates use EA to manage volatility and change and to discover and react to patterns emerging around them. For more information, please visit www.europe.gartner.com/ea.