In the future, renumbering of a customer's IP addresses will normally be imposed on a customer if that customer changes providers. If that customer is very large, the expense in changing IP numbers on dozens or even hundreds of hosts is likely to be vast. Also if the customer's applications are time critical, it will likely take the customer off the air for an unacceptable amount of time. Finally, some software applications actually require the IP number of the workstation on which they reside to be entered into the license. Change of IP number therefore could require a software license change.