This chapter covers the following topics:
Remote-access VPN services provide a way to connect home and mobile users to the corporate network. Until half a decade ago, the only way to provide this service was through dialup connections using analog modems. Corporations had to maintain a huge pool of modems and access servers to accommodate remote users. Additionally, they were billed for providing toll-free and long-distance phone services. With the rapid growth of the Internet technologies, more and more dialup mobile users are migrating to broadband DSL and cable-modem connections. As a result, corporations are in the process of moving these dialup users to remote-access VPNs for faster communication.
There are many remote-access VPN protocols available to provide secure network access. The commonly used ones include the following:
Cisco ASA supports native IPSec to provide VPN services in the most secure fashion. It also incorporates the new WebVPN technology, discussed later in this chapter.