What are VPN and VPDN and what is the difference?

VPN is known as Virtual Private Network, and VPDN is known as Virtual Private Dial-up Network. Generally speaking, VPN refers to a private network built on a public **** network, located in different terminals of the Internet, using the network's encapsulation, encryption and authentication technology to form a private network.VPDN refers to the use of dial-up terminals to build a VPN.VPN can have a VPDN and VPRN.