A Service Level Agreement (SLA) is a contract between a provider and a customer that specifies, usually in measurable terms, what services the service provider will furnish. Some metrics that SLAs may specify include: • What percentage of the time services will be available • The number of users that can be served simultaneously • Specific performance benchmarks to which actual performance will be periodically compared • The schedule for notification in advance of network changes that may affect users • Help desk response time for various classes of problems • Dial-in access availability • Usage statistics that will be provided