[aviswanathan]

One of the coolest implementations of WebRTC is a project my friend launched called PeerCDN (https://peercdn.com/) - basically allows you to reduce bandwidth costs by leveraging the resources of active users on your app.

[malandrew]

I remember looking into the feasability of something like this about 3-4 years ago when I was working on a social game with ~10 million DAU. Our bandwidth costs for static files were really really high even with a big discount from S3 because we were a heavy user. It's awesome to see that it is finally a reality.

With things like this, getting exposure isn't a matter of having the money to host your content, but simply a matter of being popular. The more popular you are, the more likely that you can offload static file hosting to those consuming your content.

[christiangenco]

Holy cow - this is amazing!

My girlfriend brought up a good point: is there any way to opt-out of seeding?

[aviswanathan]

Hmm not sure... Haven't actually tried it out yet

[ericz]

Here's one my friends (and I) are building, including a live demo: http://demo.peerkit.com/static/index_demo.html

[film42]

As soon as I saw the WebRTC demo I went looking through the bittorrent spec to see how that was done, to then see how I could do something similar. Looks like you beat me to it, but it's a powerful tool nonetheless. Just imagine Reddit only hosting their database and a single server for master replication.

[jodrellblank]

Allows active users of your app to spy on each other, seeing who connects and when.

Or maybe DOS your site, by pretending to be a PeerCDN participant but instead sending large chunks rate limited to 0.5Kb/s. The SHA1 hash check will stop them being used, but only after a long delay. People could be having a bad experience and you wouldn't even know by watching server stats.

How is the connection between peers encrypted?

[shitlord]

The problem of bad peers exists with BitTorrent as well, but it's not very effective unless you have a lot of IPs to spare. I found https://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=434346... to be an interesting read.

[fyi80]

This was a pillar of Kazaa's business model and made everyone angry that Kazaa's darknet was sucking up their bandwidth, so be sold by Kazaa.