Virtual private networks-new strategies for secure enterprise networking

Many corporations are reluctant to do business over the public telecommunications infrastructures. When they deal with outside service providers they worry about service quality, network performance, and data security. Fortunately, new IP-routed virtual private networks (VPNs) allow businesses to preserve control of their data traffic, even when routed across public networks. VPNs extend the corporate computer network out to distant offices, home workers, salespeople, and business partners. But, rather than using expensive dedicated leased lines, VPNs use the worldwide IP network services, including the Internet and service provider IP backbones. Rather than dialing in at long distance rates, remote users can make a local Internet call. Network managers can cost-efficiently increase the span of the corporate network