What are current p2p voip applications, like Skype used to be in 2003-2005?
https://www.zylstra.org/blog/2020/11/what-is-the-skype-of-now/
@ton not sure if p2p, but platforms like rocket chat, matrix, Nextcloud talk should all be at least self-hostable.
What's ultimately the goal in your situation?
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