Allow other types of public address for masternodes

[iuriguilherme]

As far as I understood from reviewing the appropriate parts in the source code, a valid IPv4 is mandatory to set up a masternode.

This really means in practice that you need a commercial VPS to own a masternode.

What would we need to allow for IPv6 (cheaper VPSs) or even better, onionV3 addresses?

Hosting a masternode using tor can be done everywhere in the world and allows for better hardware with cheaper network links than the usual VPS approach. On top of that, it eliminates the requirement for a fixed ip address which may be the most expensive part of running a masternode for some users.

[reubenyap]

@iuriguilherme We will look into this.

When we first decided to stick with ipv4, with ipv6 we were worried that people were cramming multiple nodes into a single VPS. I'll check if this is still an issue now. Onion addresses do look interesting though.

[iuriguilherme]

Depending on the financial incentive to run a masternode, ipv4s are affordable. But I wasn't part of the decision so I'm not entitled to question it.

My actual argument is in favour of awarding distribution (more nodes), which helps the network.