Local IP address in IP header information

When I see my IP on the internet it says 64.xxx.xxx.xxx (class A). So routing of my packet has 64.xxx.xxx.xxx as the source address in the header. May be after all the subnetting the receive packet c开发者_开发技巧omes to my home router, how does the home router know which private IP to send the received packets to? my private ip is 192.168.1.4 is that somehow included in the sent and received packets that my home router extracts? where exactly is it?

NAT-net work address translation and in specific NAPT-network address and port translation is what you are looking for. The router maintains the list of ports through which a packet is sent along with the private ip or something similar in a translation table.

Your router does NAT, which isn't on IP level. It's on a higher level, your router behaves as a TCP Proxy.