<P> The basic protocol for sending data over the Internet network and many other computer networks is the Internet Protocol ( IP ) . The protocol specifies that each IP packet must have a header which contains , among other things , the IP address of the sender of the packet . The source IP address is normally the address that the packet was sent from , but the sender 's address in the header can be altered , so that to the recipient it appears that the packet came from another source . The protocol requires the receiving computer to send back a response to the source address , so that spoofing is mainly used when the sender can anticipate the network response or does not care about the response . </P>
what is the difference between an ip packet and an ip address
The protocol specifies that each IP packet must have a header which contains , among other things , the IP address of the sender of the packet .