The agile enterprise requires evolvability at all layers - business, application and infrastructure. IT infrastructure systems are the foundations of IT systems in general. Their evolution has a profound impact on applications and business capabilities. Normalized Systems Theory (NS) provides a method to evaluate the evolvability of modular systems. As IT infrastructure systems can be represented by a modular structure, NS can be used to study their evolvability. An artefact is being proposed, made up of a 4-step method and summary table, to study the evolvability of a modular system representing an IT infrastructure system by means of NS. Although the artefact has been successfully applied to some IT infrastructure systems and as such demonstrating NS can be applied to IT infrastructure systems, the 4-step method requires re nement and a more rigorous translation of the NS theorems into IT infrastructure equivalents. Further research on the subject is being proposed.
The agile and morphogenic enterprise [
No application will run without IT infrastructure. IT infrastructure components
such as CPU, memory, operating system, are the bare necessities to run any
application. Changes and evolutions in the IT infrastructure can lead to serious
Combinatorial E ects - hidden coupling or dependencies in a system which
increase with the size of the system inducing a ripple e ect throughout the whole
IT landscape and breaking other IT infrastructure components, applications and
even business processes. Architecting and constructing IT infrastructure systems
which are resilient to those changes and have proven evolvability, are as
important as the creation of applications and business processes which have proven
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purposes. In: Aveiro et al. (Eds.): Proceedings of the EEWC Forum 2017, Antwerp,
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evolvability. They are an integral part of the agile and morphogenic enterprise.
Normalized Systems (NS) ( see [
Design science identi es a method, a step approach to address a problem, as a
valid artefact to apply to a problem (see [
{ Step 1: Create a relevant modular representation of the IT Infrastructure system. { Step 2: For each module of the modular representation look for manifestations of Concern, State, Version and Instance. { Step 3: Check if the manifestations found in Step 2 are compliant with the 4
NS principles. { Step 4: If there is non-compliance with one or more of the 4 NS principles, describe related Combinatorial E ects (CE).
The results of the 4 steps can be represented in the following summary table: The artefact can also be used in the opposite direction, meaning that based on observed Combinatorial E ects (CE), the violation of one or more of the NS principles can be identi ed and this violation can be associated to a manifestation of Concern, State, Version and Instance in a module representing a function and/or construction component of an IT infrastructure system.
In [
These 6 use cases have been evaluated by an expert team (13 members) which
represent the Knowledge Base in the Design Science framework of Paul
Johannesson and Erik Perjons [
The previous section shows that the proposed artefact can be used to apply NS on IT infrastructure system, and can thus be used to test evolvability of the IT infrastructure system. However, the di erent steps of the artefact method do require extensive knowledge of the IT infrastructure system under investigation and a good understanding of what the manifestations of Concern, State, Version and Instance may look like in the IT infrastructure system.
Further research is required to create a standardized meta model which can be used to make a modular representation of an IT infrastructure system. A deeper understanding of the meaning of Concern, State, Version and Instance in an IT infrastructure system needs to be further investigated. Based on this deeper understanding, the transformation of the 4 NS theorems into applicable Normalized Infrastructure Systems Theorems (NIST) can be created. The current artefact summary table must be improved by having a standardized way to describe manifestations of Concern, State, Version, Instance and the description of the CE. The proposed artefact improvements will lead to a more systematic approach in applying the artefact.
Once a transformation of the 4 NT theorems into applicable Normalized Infrastructure Systems Theorems (NIST) is available, the research can shift towards using those as input for an expander which will, based on a standardized functional description of an IT infrastructure system, expand code which can be deployed on a Software De ned Infrastructure Platform (like AWS, Azure, Google), resulting in deployable and evolvable IT infrastructure systems.