There are some strong analogies between town planning and service-oriented architecture, which make it reasonable to translate Christopher Alexander's ideas into the SOA domain.
1. The distribution of design. Detailed design decisions are taken within different organizations, each following its own agenda (e.g. commercial or political goals).
2. The constancy of change. Elements of the whole are constantly being redesigned and reconfigured, and new elements are constantly being added. Structures must evolve in robust ways.
3. The need for progressive improvement. Each design increment should not only make local improvements, but should have a positive effect on the whole.
4. The recursive nature of the architecture. Similar design tasks must be carried out at different scales (levels of granularity).
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Richard C. Murphy: Christopher Alexander's theory of centers helps explain the essential properties of service-oriented architectures. (FTP Online, March 2004)