Implementation of GRE Over IPsec VPN Enterprise Network Based on Cisco Packet Tracer

Abstract

Along with the increasing prominence of network security problem, VPN (Virtual Private Network, VPN) technology provides a solution of economic remote access for the enterprise. As the IPSec protocol is able to provide the highest level of security, using IPSec VPN to build security Intranet has become a trend. Since the IPSec (Internet Protocol Security) does not support the encryption of multicast and broadcast packet, GRE (Generic Routing Encapsulation) tunnel is needed to encapsulate multicast and broadcast packets to unicast packet. By encrypting the GRE with IPSec, the data security is guaranteed and the problem of VPN scalability is solved.