They should be able to unless the ISP is blocking external traffic to Node A or Node B.
Given that both JIO and Airtel appear to be mobile internet providers, I wouldn’t be surprised if individual subscribers are firewalled from the internet.
I would suggest upgrading to v0.4.19 and enabling the experimental AutoRelay feature on your nodes and bootstrap node. In short,
- On Node A and Node B,
ipfs config --json Swarm.EnableAutoRelay true - On Node C,
ipfs config --json Swarm.EnableAutoNATService true
If that doesn’t work, you can try connecting Node A and Node B manually through the relay (Node C) as described here.