I let about 10 family and friends connect directly to my home server. My firewall blocks everything except for these 10 IP addresses.
I did get tired of having them figure out their IP address so now I just tell them to access a dummy page page on my external VPS and I check the web server log to see their IP to add to my firewall config.
So in other words IPv4's shorter addresses didn't help at all?
And also it seems like a lot to sacrifice in order to make something marginally more helpful about once or twice a year.
Also why would you say it over the phone? Would you not ask them to email or IM it? I can't count the number of times passwords and names have been misunderstood over the phone. Numbers? Basically always at least one number is misheard.
I let about 10 family and friends connect directly to my home server. My firewall blocks everything except for these 10 IP addresses.
I did get tired of having them figure out their IP address so now I just tell them to access a dummy page page on my external VPS and I check the web server log to see their IP to add to my firewall config.