Impersonation is a big issue in federated social networks. I can't have my username registered in all possible instances of mastodon. So someone else could impersonate me on another instance, follow you, and start saying or doing things that I don't approve of. This is dangerous and has been well known for the last couple of years. The solution does not look easy to me.. plus it is hard to argue that the solution is non-technical

@guneetnarula you need to publish a public pgp key its as simple as that. Only you can then sign messages with that key and others can verify

@guneetnarula look up mailvelope you can do it in a browser extension