KEYnote 36 English - Fall 2018 | Page 8

L I C E N S I N G License Server in High Availability Environments 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 revenue. Good Answers 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- vice disruption. ■ ■ License checks: All purchased licenses are reliably available – no more, no less. 8 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. License Structure 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 same properties. Similar CmContainers 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- 59885682. 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.