First, although the DDN technology can realize the interconnection between enterprises, but the rent is expensive; ADSL Broadband Although the price is low, but it can only be applied to enterprise access to the Internet, can not achieve the interconnection between enterprises. VPNs can help to achieve an economic and secure interconnection between enterprises, that is, enterprises can use the ubiquitous Internet to achieve convenient and efficient exchange of visits.
Second, although the Internet provides the convenience for enterprise to realize data access, its high openness and loose management structure also make the enterprise face serious network security problem. The user can encrypt the data transmitted through the VPN tunnel by using encryption technology to ensure that the data is only understood by the designated sender and receiver, thus ensuring the privacy and security of the data.