Does this mean it is impossible for anyone to know what peers are pinning certain data?
In the case of nodes pinning banned/illegal/copyrighted content, does this mean there is not way for authorities to determine which nodes are hosting the content?
As far as I know, yes. But pinning is not a prerequisite for providing a given piece of content.
Government censors, authorities, copyright trolls, etc can currently get an idea of which nodes are hosting or requesting content the same way anyone else can.
See who is advertising that they can provide a piece of content
Try to retrieve the content and see who sends it to you
Sniff DHT traffic to try to determine who is requesting content
Are there any separate tools through which we can sniff DHT traffic?
Is it possible to that Node B (peer ) is able to know that Node A(Self) is requesting some content over the network.
I’m not sure what all is available. I know you can see the flurry of activity (among other things) from your node’s perspective by running the daemon with the --debug flag.
Given that Node A necessarily needs to ask other peers it’s connected to if they have content it wants, I think there’s a chance that Node B would know Node A is looking for something – especially if they’re directly connected.