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Comment by deanCommie | Hacker News Reader

Genuine question coming from a lack of understanding of building a many-to-many video chatting app.

Wouldn't you want to send the data peer-to-peer between the users rather than funneling everything through the Zoom server?

You'd get better latency, and you wouldn't have to pay for the network streaming costs...

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Peer to peer has been dead for more than a decade. Computers are all behind firewall/NAT, they can't connect to one another. Mobiles are behind whatever is the mobile network nowadays, it's outbound only, nothing can connect in.

> Peer to peer has been dead for more than a decade.

Source? Some apps like bittorrent have increased in the past decade, have they not?

I shall say peer to peer in the context of legit software like video conference, not for downloading movies.

Peer to peer simply doesn't work since NAT. Skype used to be peer to peer but they backpedaled a while ago because this and more reasons that simply made p2p obsolete and broken.

It's too long to cover in one message. Would you be interested if I write a blog post? How peer to peer architecture became obsolete and why no software is using it.

> Would you be interested if I write a blog post? How peer to peer architecture became obsolete and why no software is using it.

Ya, I'd be interested in reading that! Could you address why it wouldn't work with NAT the same way bittorrent deals with it? I'm probably missing something, but I don't see why bittorrent can work so easily but video conferencing cannot. thanks

Edit: Does bittorrent require you to port forward? I didn't think it did, but I haven't seen it configured in years so maybe I am forgetting that step

If I am understanding the premise:

In a scenario of 12 people video chatting around the world, I don't believe you could guarantee consistent high-speed connections between the involved parties.

Making the connection is the hard part. The vast majority of computers and mobile devices basically do not have a routable/public IP address.

Teredo tunneling was one of the coolest solutions to this problem, providing both NAT-busting and IPv6 support but unfortunately it never gained popularity.

I would read that blog post in a heartbeat.

BitTorrent typically requires you to open a port on your router. For home use you just turn on UPnP but good luck getting that to work on a corp network.

Not quite true.

Some machines can't be reached. Many others have UPnP capable routers and can reconfigure NAT for port forwarding on the fly.

Additionally more and more users have IPv6 at home. It's now high enough to be worth trying along with other techniques like STUN.

Peer to peer may not work on the mobile networks you're on, but it works on many.

So how does bittorrent work, then?

In the best case, yes. In the worst case, users can't connect -- which goes in contrast with the "It Just Works" use case for Zoom.

P2P is great if you're small, but eventually it makes sense to do client-server with servers in the data centers to get that extra 10% of customers. Skype and Spotify are both formerly-P2P applications that went client-server.

In practice, you end up relaying a lot of traffic through TURN servers due to NAT issues, plus most enterprise-grade platforms connect to conferences as peers for recording purposes, and allow for server-sourced multicast for things like presentations with large audiences, or to allow synchronized video without lag or quality issues.

I don't think that's always or even often practical given constraints such as: firewalls, NAT, and varying bandwidth limitations of clients.

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