L I C E N S I N G
License Server in High
Guaranteeing optimum availability, while keeping a strict count of the purchased licenses, is a constant cause for friction
between software makers and their users. With the Triple Mode Redundancy system, Wibu-Systems has a solution to this
conundrum e.g. for industrial users that works without disclosing license calls and without having to rely on trust alone.
A Fictional Example
Dr. Schwabe, head license buyer at a renowned
maker of solar panels, has a habit of calling Mr.
Zenz once a year. Every time, it is about the same
issue: The quality assurance software works just
fine, but then there are sporadic problems with
reaching the license server. What is the point of
licensing, if it causes problems, he wonders? His
company is a company that people can trust.
But Mr. Zenz knows better: Only last month, a
support incident revealed that a company used
more licenses than it had paid for. The goodwill
licenses made available to cover for some recent
server issues almost led to a major loss of valid
This year, Mr. Zenz finally had an answer that
Dr. Schwabe could not ignore: Wibu-Systems
is offering a solution that combines the best
of both worlds:
■ ■ High availability: Server outages or other
problems do not have to mean a real ser-
■ ■ License checks: All purchased licenses are
reliably available – no more, no less.
As a Triple Mode Redundancy system TMR Server
Setup, the concept works with a combination of
a 2-out-of-3 licensing concept and tried-and-
tested data center technology. Luckily, Mr. Zenz
had already migrated the licensing system
to the new Universal Firm Codes, which is a
precondition for TMR licenses.
Every license is created in triplicate and given
a special ID, the TMR ID, as an additional
property to go with the license count. The TMR
ID is used as a definite identifier for all three
licenses. The firm code, product code, and
TMR ID need to match for all three licenses
to come together and form one TMR license.
Ideally, consecutive numbers are used for each
new TMR license.
There is no need to test whether other
properties of the product items match, as this
would only lead to more complications with
later updates. However, it helps if all three
licenses going with a TMR license have the
The three licenses are placed into three sepa-
rate CmContainers that have to have the same
CmActId, as the TMR Server Setup can only
allocate CmContainers with the same CmActId
to a virtual CmContainer. This virtual container
is the only one seen by the user, with nothing
indicating that it is a virtual receptacle of three
separate CmContainers. Virtual CmContainers
have fully configurable, typically random serial
numbers with a new mask byte 131, e.g. 131-
The same approach naturally also works with
three CmDongles, which would then also
form a virtual CmContainer with a serial number
starting with 131.
The 2-out-of-3 Rule
For a TMR license to be valid and available, at
least two of the three related licenses have to
be available. If only one of the three is there,
the TMR license will not make an appearance
in the virtual CmContainer.
A CmContainer with only one of the constituent
licenses is of no use to anyone: The CodeMe-
ter-Server would bar a license with a TMR ID from
being used in this case. In effect, such a license
could only be used in a full TMR Server Setup.