Ensuring that someone is who they say they are is key to the security of your business. With users accessing networked PC's and potentially accessing your network remotely via VPN the consequences of an unauthorised individual gaining access to your network could be huge.
Weak user passwords, spyware key loggers, easily stolen or lost mobile computing devices and poor general security awareness leading to sharing of passwords and increased likelihood of "shoulder surfing" password compromise makes it relatively easy for someone unauthorised to access your network or resources.
The use of 2-factor authentication systems reduce that risk requiring, for example, a PIN and token combination to authenticate to a system.
Authentication solutions have many applications and may be typically be used in conjunction with Remote Access and SSL VPN solutions.