Why IP address can't be faked like MAC address?

Question

I'm still unable to figure out why IP whitelisting works so well... How it's possible to have an unique ID(IP) without encryption?

just-juan-post · Accepted Answer

RoutingIf I create AWS VM with IP of 1.1.1.1 no traffic will be send to it because all other systems on the Internet have routing tables that point to the real 1.1.1.1.I can send fake traffic from that VM as 1.1.1.1 but it won't get far and no one will send responses.