The Hack Dissected
Stepan pulled out his access token and typed in the six-digit random number from the token and the four-digit PIN he had memorized. Soon he had established an encrypted connection to the office back in Zurich, Switzerland. He opened his e-mail software and found the message waiting for him. (p. 4)
In the prologue, Stepan used an RSA token to authenticate himself into his office network over a virtual private network (VPN) connection. A VPN allows for someone to connect into their home or office network from afar through a very strongly encrypted connection. A VPN allows people to check e-mails and view network files without third parties being able to view the network traffic.