[libnice] Audio/Video streaming through libnice

[jags gediya]

Hi All,

I want to stream audio/video between two peers in the different network.
By searching on internet, I have found libnice suitable for my requirement.
I have some doubt regarding libnice.

1. Can STUN/TURN/ICE traverse the Double NAT?
2. For my need, I may need to use gstreamer as provided in the below link.
    http://nice.freedesktop.org/wiki/GStreamer/
but i am not understanding those steps, and how to use them in the application.
Has anyone implemented the same, can share the snippet of their code?
Is there any sample code available for audio/video streaming as per
steps described in above link?