1
I am not very clear about the detailed aspect of the ports.
My concern is, is it possible for the ISPs to block these ports of bitcoin clients and therefore censor bitcoin, even if the internet is available. If they can, how bitcoin solve it. If not, please give me an understandable explanation.
2
Is it possible for the ISPs to block these ports of bitcoin clients?
Yes, it is. It is fairly trivial for most ISP's to control ports.
And, therefore censor bitcoin?
Not easily. It is possible to configure Bitcoin Core to operate over the Tor network. Tor itself can be configured to run even behind a fascist firewall (it has settings labelled such), although, I encourage all to only act in a lawful manner.
Similarly, it is possible to configure Electrum wallet to operate over Tor.
If I use tor, the port is still 8332 and 8333? – an offer can't refuse – 2018-04-28T02:46:15.760
If all the sudden, all countries form a consensus and decide to block the two ports, just like every country define drug as illegal, will tor still be useful in this scenario? – an offer can't refuse – 2018-04-28T02:57:13.377
@buzhidao Port 8333 is used for connecting between Bitcoin nodes. If using Tor, the Bitcoin Core application uses Tor to make a tunnel through the Tor network. This tunnel is not on those ports. It is possible for two nodes to communicate without ever needing those ports outside of the node. Port 8332 is not needed to be shared. – Willtech – 2018-04-28T05:04:32.403