Introduction

Networks are no longer restricted to the confines of a single location or even a small group of locations. Users can, and do, connect to remote networks from virtually anywhere. The ability to remotely access networks has changed the way we work and do business. Today, anywhere/anytime access to computer networks is an expectation rather than a bonus. Whether a user is working from home, his or her car, or a branch office, the ability to access the corporate network has become a critical requirement.

Modern network and workstation operating systems facilitate remote access by providing the means and methods to do it. By using remote access capabilities, it's possible to create a secure, transparent connection that lets remote corporate users feel as if they were operating from the local network.

Traditionally, remote access has been achieved by using a modem and a dial-up connection. Although this method is still widely used and is by far the most popular method of remote connectivity, new technologies continue to emerge, increasing the variety of ways that networks can be accessed remotely. Technologies such as fixed wireless, Internet access using cable, and Digital Subscriber Line (DSL) have opened up new possibilities for remote access through their increased speed and reduced costs. These high-speed remote access methods mean that instead of just using the connection to transfer a file or two, remote workers can use a variety of technologies such as videoconferencing.

Regardless of the technique used for remote access or the speed at which access is achieved, certain technologies need to be in place in order for the magic to happen. These technologies include the protocols both to allow the access to the server and to secure the data transfer after the connection is established. Also necessary are methods of access control that make sure only authorized users are using the remote access features.

All the major operating systems include built-in support for remote access. They provide both the access methods and security protocols necessary to secure the connection and data transfers.

This chapter focuses on the protocols and services used to establish and secure remote network access. It begins by looking at the remote access protocols and the protocols used for security. Finally, the chapter examines two remote access methods—dial-in access and virtual private networks (VPNs)—and the protocols they use to establish and secure remote connections.