Can I use WebRTC to open a UDP connection?

问题:

We need send data to our users' devices using the TFTP protocol, which is a simple FTP-like protocol that works over UDP.

Since we can't open a UDP socket using javascript, we have been using our server as a proxy, sending the data to our server and opening a UDP connection from the server to the device. That does have the drawback that our users need to learn about NAT and configure port forwarding.

So the question is, could we use WebRTC to open a direct UDP socket to send and receive between the browser and the devices?

http://www.webrtc.org/reference/webrtc-internals/vienetwork#TOC-SendUDPPacket suggests that we could send some raw UDP data over the socket (that is, if it's possible to access that layer over javascript. i'm not sure about that), but I see no way to fetch a raw UDP response.

Any help much appreciated

回答1:

No. There are too many security issues allowing WebRTC to send to a random address/port - we have to make sure it doesn't work as a DDOS platform, so we require the target to implement ICE as an implicit permission to send data, and we also don't allow sending arbitrary data, just SRTP mediastreams and data in DataChannels (over SCTP over DTLS over UDP+ICE).

回答2:

No, you cannot send raw UDP data using WebRTC like that.

The ViENetwork lib where you can find the SendUDPPacket method is used inside Chrome to handle packet transmissions, Windows QoS support and other network settings, but you don't have direct access to it.

One of the main features of WebRTC is the Data Channel that will bring the possibility to establish a peer-to-peer connection between two browsers, to allow raw data to be exchanged. This is still under construction in Chrome and Firefox as you can see here.

This can be what you are searching for, as you can establish a connection to send raw data and you will only have to worry in find a way to establish this connections to your other endpoint, if that's what you want.