Rm ostel - Not maintained

README.md

@@ -490,7 +490,6 @@ Mailing lists servers and mass mailing software - one message to many recipients
 - [FusionPBX](https://www.fusionpbx.com/) - Open source project that provides a customizable and flexible web interface to the very powerful and highly scalable multi-platform voice switch called FreeSWITCH. ([Source Code](https://github.com/fusionpbx/fusionpbx)) `MPL-1.1` `PHP`
 - [Kamailio](https://www.kamailio.org/w/) - Modular SIP server (registrar/proxy/router/etc). ([Source Code](https://github.com/kamailio/kamailio)) `GPL-2.0` `C`
 - [Kazoo](https://2600hz.org/) - KAZOO is an open-source, highly scalable software platform designed to provide carrier-grade VoIP switch functions and features. ([Source Code](https://github.com/2600hz/KAZOO)) `MPL-1.1` `Erlang`
-- [Ostel](https://dev.guardianproject.info/projects/ostel/wiki/Server_Documentation) - Secure SIP telephony setup with ZRTP encryption. `GPL-3.0` `Ruby`
 - [Routr](https://routr.io) - A lightweight sip proxy, location server, and registrar for a reliable and scalable SIP infrastructure. ([Source Code](https://github.com/fonoster/routr)) `MIT` `Javascript`
 - [SIP3](https://sip3.io/) - VoIP troubleshooting and monitoring platform. ([Demo](https://demo.sip3.io), [Source Code](https://github.com/sip3io/)) `Apache-2.0` `Kotlin`
 - [SIPCAPTURE Homer](https://www.sipcapture.org/) - Troubleshooting and monitoring VoIP calls. ([Source Code](https://github.com/sipcapture/homer)) `AGPL-3.0` `Angular/C`