Research Matrix.org as a signaling server alternative to PeerJS Server

[ivelin]

Currently we use a fork of PeerJS Server as the signaling server for peerfetch clients. This works fine, but requires hosting a signaling server.

It is also a single point of failure, although this is not a big concern, because it only has ephemeral state and it takes very little to recycle a bad instance and start a new one with minimum disruption to the peerfetch network. Each peerfetch edge node periodically re-registers with the currently active signaling server, so a restarted server will restore the network to a fully working state within a few seconds.

We can investigate whether the global matrix.org network is a more secure and resilient alternative with lower maintenance cost.