In this paper

starting from the theoretical study of the key technology for VPDN business of group customer

the L2 TP tunneling protocol and the L2 TP over IPSec VPN protocol is provided. The networking planning of VPDN business of group customer is presented

combined with corporate client business security requirements without increasing 4G core network infrastructure equipment. Accordingly

the performance testing of network connectivity

IPSec encryption/decryption function

video surveillance and uploading and downloading operation is executed

which come from demand for customer perception. The testing verification through the program is feasible.