[Candidate](https://www.rfc-editor.org/rfc/rfc5245#section-15.1) attribute in a SDP provides connection address of the candidate. Which looks like this:

```
a=candidate:4022866446 1 udp 2113937151 192.168.0.197 36768 typ host

```

I want to know how does sdp collects information about my local ip.

It'd be great help if there's any specific webrtc code to look at. And, if it is possible to look at local IP, can sdp know my default gateway ?