Our quick primer will help you assess the three main types of VPNs as applied to Remote Access outsourcing, Site-to-Site connectivity, and Extranet connectivity.

 Remote-Access VPN

Employees who need to access corporate headquarters remotely can dial into an Internet or network service provider's POP (point of presence), establish a tunnel through the corporate firewall, and authenticate themselves to gain access to the corporate network.

Using a VPN for remote access enables users to transmit and receive corporate information over the Internet. Cost savings are realized by eliminating the need to make a traditional long distance call or maintain a local business metered line. Further savings come from reducing the operational costs associated with supporting remote users, modem pools and remote-access servers, and by eliminating the need for separate telephone lines for dial access.

 Site-to-Site VPN

As with remote-access VPNs, a site-to-site VPN connects branch offices to corporate headquarters through tunnels that transport traffic over the Internet or via a provider's backbone.

A VPN for site-to-site connectivity reduces communications costs by allowing branch offices with multiple access data links to move traffic over the existing (and lower priced) Internet access connection.

 Extranet VPN

A VPN-based extranet uses VPN access control and authentication services to deny or grant customers, trading partners and business associates access to specific corporate information. The outsider would get to the corporate firewall by tunnelling across the Internet or a service provider's network. The ability to get behind the firewall is controlled by the VPN access control services.

By managing levels of access to an extranet, companies can give select customers privileges they did not have before. This can improve customer satisfaction while reducing employee involvement.