The biggest difference with the alternatives you mention is that Vialer seems to be an actual application while the others are more lower-level infrastructure /

The biggest difference with the alternatives you mention is that Vialer seems to be an actual application while the others are more lower-level infrastructure / frameworks to build such an application. I've been doing a comparison of these some time ago and here's what I remembered: There are 3 ways of doing webrtc: - Mesh -> everybody sends and receives to every other participant. -> Needs almost no infrastructure, but obviously doesn't scale well. - SFU -> acts as a relay, so people only need to have 1 upload, but still download everybody -> Needs some infrastructure, scales better than mesh but still limited by amount of downloads per participant - MCU -> makes compositions in the cloud so people only have 1 upload and 1 download -> Very expensive in terms of infrastructure, infrastructure is hard to scale, but least amount of traffic and processing by participants. These seem to be the most well-known solutions: - Kurento -> was very complete, but is more or less dead since Twilio bough the team (they had some recent activity, but are really lagging behind now). - Janus -> a set of building blocks to build which can be used to build an SFU or MCU. - mediasoup -> sfu with node bindings. Was very new when I did my comparison, no idea how mature it is now. - Jitsi -> Very nice SFU, bought by Atlassian, but they still put a lot of work in the open-source version (contrary to what Twilio did with Kurento). Highly recommend if you want to deploy your own SFU. - Intel WebRTC -> both sfu and mcu, but documentation is limited and it specifically targets intel platforms (originally based on 'licode' which is yet another alternative) Next to that you'll also need turn and stun servers if you want to deal with any business networks (coturn seems to be the go-to if you need a turn server). CPAAS: Despite the 'open' in the name, opentok is a closed platform from the leading webrtc provider (tokbox). They provide the server infrastructure (usually SFU and Turn servers). Some alternatives are twilio video, vidyo, temasys. We eventually went for a CPAAS (tokbox), happy with them so far. We also use Janus for some customer-specific integrations. Note that the summary is very, very limited. You may also care for a lot of other stuff, such as: Sip integrations, Broadcasting to HLS or RTSP, Recording/Archiving, Security practices, GDPR Compliance, Licenses, Browsers support, SLA's, ...