3.The process of modifying IP address information in IP packet headers while in transit across a traffic routing device is known as().
NAT(Network Address Translation)
VPN(Virtual Private Network)
ARP(Address Resolution Protocol)
QoS(Quality of Service)
NAT（网络地址转换）是在报文经过路由器时，修改其源或目的IP地址的过程，常用于私网访问公网。