Software publishers utilize myriad different license metrics to
determine what kind and quantity of particular licenses their
customers are required to purchase. Some are relatively
straightforward, such as "one license per server" or
"one license per user." Others can be more complex, such
as "one license per each virtual processor core...Subject to a
four-core minimum...With licenses sold only in 'packs' of
two...And you better make sure you're purchasing the right
software edition." Most of these metrics – especially
the more complex ones – make lots of sense if you are the
publisher, usually less so if you are the licensee.
However, once a company reaches a certain size, even the
"simple" metrics can become exceedingly difficult to use
in the real world. Hardware inventories can be difficult or
impossible to gather for companies with dynamic, distributed
computing domains. Users accessing particular programs on servers
(or licensable options within those
