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Open-source licenses.

Celvesta is built on open-source software. We are grateful to the people who build and maintain it.

Celvesta is an independent service. We install, brand, configure and manage the software below on a separate server for each client. Celvesta is not made, sponsored or endorsed by any of these projects, and their names belong to their owners.

Each project is released under its own open-source license. The full license texts are included with the software and published in each project's source repository.

  • SEMS

    SIP Express Media Server, the SIP signaling and media engine of the switch. source code

  • Kamailio

    SIP server used as a proxy and load balancer in front of the switch. kamailio.org ยท source code

  • Redis

    In-memory data store used by the switch for fast lookups. redis.io

  • PostgreSQL

    Database for routing, billing and call records. license

  • Ruby on Rails

    Framework behind the admin panel and customer portal. rubyonrails.org

  • Debian GNU/Linux

    Operating system on every Celvesta server. licenses