(1) (Open Source Software) Software that can be modified and recompiled by the user. See open source.

(2) (Operations Support Systems) An umbrella term for software that supports the telecommunications industry, but is not involved with the routine network operations of transmitting and switching data. OSS includes inventory management, CRM, middleware, performance monitoring, test & measurement and provisioning. B/OSS includes the billing. For more information, visit www.nextgenerationservices.com.