Evolution Process

As customer and business needs change, the specification needs to evolve continuously. To address the need for improvement the project has been setup in an agile manner.

Basic Concepts

A specification as a product which is managed as follows:

  • We have a backlog of improvements where everybody can contribute.

  • An improvement addresses a need and solves a problem, thus producing value.

  • The Sales Progress Group (SPG) Working group (NRT/IRT/NT groups) identifies the business needs on behalf of the railway undertakings. The business representatives prepare the new requirements with Chairs of OSDM technical Working group. The output is a functional specification document to be examined by the Personal Expert Subgroup (PES) (input). On the side the distributors’ side, the business needs are identified by Eu Travel Tech (ETT) representatives.

  • The OSDM executive committee (Chair: Marc Guigon & Vittorio Carta) prioritizes the backlog based on the value for the railway customer and the railway sector as a whole. The committee is a fair representation of the parties involved, thus railways and distributors and others.

  • The OSDM technical working group (Chair: Clemens Gantert & Andreas Schlapbach) designs and implements improvements to the standard. Thus, it is responsible to translate the functional specification identified by the SPG/PES and ETT into a document of technical specification. To stay focused, the work in progress should not be larger than seven items. The working group takes special care not to break existing implementations, thus securing investments made by all the parties.

  • The PES endorses the functional and technical specifications prepared by the OSDM Technical WG, preparing the agenda of the OSDM executive committee. Similarly, ETT endorses the improvements prepared.

Illustration of the concepts:


Structure of an Improvement

An improvement is structured similar to an epic in the SAFe framework as follows:

  • Name: Short name for the improvement

  • Owner: Name of the owner

  • Description “For customers who do something the solution is a improvement that provides this value unlike current solution or non-existing solution our solution does something better.”

  • Business Value: The business value which is generated after the improvement has been implemented (low/middle/high).

  • Business Outcomes: The measurable benefits that the business can anticipate if the epic hypothesis is proven to be correct.

  • Leading Indicators: The early measures that will help predict the business outcome hypothesis.

  • Non-functional Requirements: If a business requirement has critical non-functional constraints they should be noted here.

  • Specification Effort: An assessment of the effort to specify the improvement (EXTRA_SMALL, SMALL, MEDIUM, LARGE, EXTRA_LARGE).

State of an Improvement

An improvement takes the following steps:

  • An improvement is in the initial state proposed.
  • The steering board then decides which improvements to analyze based on their business value → state accepted for analysis.
  • The technical experts then analyses the improvement and determine its complexity (low/middle/high). After their work the improvement is in state analyzed.
  • The steering board decides which improvements are to be implemented based on a transparent prioritization model (e.g. Weighted Shortest Job First) → state accepted for design.
  • The technical experts then design the solution, thus the API, the documentation and the test sets. After their work the improvement is in state designed.
  • The steering board releases major, i.e. breaking changes → the improvement is published.

Working Mode

The technical working group meets online every Friday from 9:00 to 11:00. Participation is open to everybody and highly encouraged. If you wish to join, please contact Schlapbach Andreas.

The meeting minutes as well as future improvements are documented in the GitHub Wiki.

Road Map

The specification is improved in fixed-length time boxes similar to a program increment in the SAFe framework. See the OSDM Wiki for the roadmap.