Announced earlier this month and talked about for at least a year (I think they mentioned this at the 2007 Dev Summit), ESRI is moving away from socket licensing to using the number of cores on the server.

Through November 30, 2007, ESRI licensed server software based primarily on the number of physical sockets on the server which are being utilized by CPU chips. These CPU chips can have 1 or more processing “cores,” each core providing additional computing power for the CPU chip. Licensing requirements and fees for ESRI server software are based on the combination of the number of utilized sockets on the server and the number of cores on each CPU chip.

To address recent changes in the server hardware markets, ESRI has adjusted the licensing and pricing model for ESRI server software to be based only on the number of cores on the server. This adjustment simplifies the process of determining the appropriate license requirements and license fees, especially for new hardware configurations that are continuously being introduced.

Now before you get all worked up that this will cost you more money…. DON’T. Your maintenance will not change because ESRI is adjusting the pricing model as well. It will mean you’ll have a much easier time determining your license and fees using the new chart provided by ESRI.