A2Billing is a free and Open Source telecom switch and billing system capable of providing and billing a range of telecom products and services to customers such as calling card products, residential and wholesale VoIP termination, DID resale and callback services.
Original codebase is copyright (c) 2004-2015 Star2Billing S.L. <info@star2billing.com> Portions of the code are copyright (c) 2022-2024 RadiusOne Inc.
A2Billing is licensed under AGPL: http://www.gnu.org/licenses/agpl.html