From railML 2 Wiki
Jump to navigation Jump to search
🗒️ This page is mirrored from page Dev:Versions in The railML® 3 wiki.
RailML Trademark RGB V2.png
XML Railway exchange format
Latest release: 2.5
(September 1st, 2021)
Main Menu
XML tree
UML diagrams
Use cases
Versions & Changes
railML® 3 WikiRailTopoModel® Wiki
🗒️ The subject of this article are official version releases. If you are interested in accessing, setting and naming developer versions, see dev:versioning.

Release Policy

Major Release

Commited changes have affects on XML-instance files and should be announced in advance in corresponding railML® newsgroups.
Tagging a major release after railML® conferences' consensus
Version number
Increasing first digit, e.g. version="2.0"
Changing the year in the namespace string, e.g. xmlns=""

Minor Release

Commited changes have no affects on XML-instance files, but on other coordinators' XSD-schema files.
Commits of new elements, types and/or attributes are allowed.
Tagging a minor release after railML® coordinators' consensus
Version number
Increasing second digit, e.g. version="2.1"
Up to railML® 2.x the year and version changed in the namespace string. From railML® 3.1 onward the year is no longer part of the namespace string. In consequence the version is changed with each minor version, e.g. xmlns="".


Corrigendum commits and cosmetic changes with no affect on XML-instance files are allowed.
Tagging a corrigendum after railML® coordinators' consensus
Version number
Increasing third digit, e.g. version="2.0.1"
No influence on the namespace string, e.g. xmlns=""

Unofficial/Developers Version

Depending on the current policy only Subversion commits for corrigendum, minor or major railML® releases are checked into the repository for further feature development.
User requirements from the forum are kept in the railML® ticket system: For railML® 2 they can be found here; for railML® 3 they can be found here. The railML® coordinators prioritize them, code each single topic in a railML®ish way and commit changed files into the Subversion repository. See also Officially released versus developer version for more information.
Version number
Each atomic Subversion commit is tagged with the increasing Subversion number. The last official version number is expanded by the Subversion release number. e.g. version="2.1r460"
No influence on the namespace string, e.g. xmlns=""

Version numbers and corresponding namespaces

How to describe the version number of a railML® file? Or to find out which version a railML® file belongs to?

Version numbers

You will find a version attribute in the railML® root element <railml> as well as in the root elements of the sub-schemas as <infrastructure>, <rollingstock>, <timetable>. This attribute is to be used for the version number of the railML® schema the XML file is based on.

Major, minor and corrigendum version are separated by a dot, the release number is separated by r. Corrigendum and release number are optional:

<major version>.<minor version>[.<corrigendum>][r<release number>]

The following rules apply:

  • The release number is required to be omitted if a railML® file is based on an official released railML® version. This applies to railML®'s release numbers
 * 2.0r270 has to be given as 2.0,
 * 2.1r409 has to be given as 2.1,
 * 2.2r602 has to be given as 2.2,
 * 2.3r668 has to be given as 2.3,
 * 2.4r862 has to be given as 2.4,
 * 2.5r1327 has to be given as 2.5 and
 * 3.1r989 has to be given as 3.1, all respectively without release number.
 * Since 3.2 there is no usage on SVN anymore as switched to Gitlab and therefore no more release number.
  • The release number shall be considered mandatory in all other cases, e. g. if it is "an unofficial release version" but an intermediate. For more information on the relevance of intermediate versions see Officially released versus developer version.
  • The attribute version of the root element of the railML® file shall be considered mandatory. If the root element of the railML® file is <railml>, the attribute version of the subsequent elements <infrastructure>, <rollingstock>, <timetable> are optional. If they are used, they have to be identical to the version of <railml>.
  • The corrigendum release number is mandatory, if the release is tagged this way. Otherwise it shall be ommited.

This official railML® version number should not be confused with an implementation dependent software version in the metadata elements dc:format and/or dc:identifier.

Namespace declarations

As above mentioned the XML namespace does also change with the railML® version. The following table shows this relationship for all official railML® versions.

railML® version number railML® namespace string remote schema location HTTPS access
1.0 no namespace different schema locations for sub-schemas no
1.1 no
2.0 yes, optional
2.1 yes, optional
2.2 yes, optional
2.3 yes, optional
2.4 yes, mandatory
2.5 yes, mandatory
3.0 (alpha & beta only) Alpha & Beta phases finished no
3.1 yes, mandatory
3.2 yes, mandatory

The XML file should declare the same XML namespace (identical string) as defined by its corresponding XML Schema. For general information about namespaces see Defining namespaces and validating railML® files.

A railML® file based on an intermediate release with remote schema location shall refer to a commit on our development platform (link to the railML® website). This is

  • for railML® 2:<commit hash>
  • for railML® 3:<commit hash>

For instance commit 5f735749 (railML® 2) can be found under It corresponds to commit [416] of our legacy Apache Subversion Control (Wiki banner.png) (SVN).
Commit 6e7d61fa (railML® 3) can be found under and corresponds to SVN commit [1026].


All currently supported railML® versions are licensed dually under a restricted form of the Creative Commons licence (external link) CC-BY-NC-ND and (for certified programmes) in a commercial licence. To learn more about the licence terms see (link to the railML® website).


railML file of official released railML version 2.0, remote schema location:

<?xml version="1.0" encoding="UTF-8"?>
<railml version="2.0"

railML® file of intermediate release SVN #416/commit [5f735749] (between official releases 2.1 and 2.2), remote schema location:

<?xml version="1.0" encoding="UTF-8"?>
<railml version="2.1r416"