Hi Rioevcfenix,
127.0.0.1 is what is known as the loopback address - anything sent by a machine to 127.0.0.1 ends up at that same machine. You might have seen a t-shirt saying “There’s no place like 127.0.0.1”. So, yes, if you are hosting IVC then 127.0.0.1 is always valid as an address in the client on the same machine. You might see 0.0.0.0 suggested as well, as (in the context of IVC at least) it can be translated as “all the addresses on this machine”, so it would cover any set of IP addresses you have (wifi, ethernet, VPN endpoints etc)
You can use your own IP address in the client (if you are hosting IVC) but 127.0.0.1 is so much easier to remember.