Chapter 7 Firewall : Security policies : Identity Based Policies
  
Identity Based Policies
Identity based policies are ones in which there is the additional component of either an account identity or device identity. The inclusion of one or both of these components adds an extra dimension of complexity to working with these policies in the context of the other policies so while the extra security and granularity of control are beneficial, extra care must be taken when configuring the policies themselves and how they are positioned in the policy sequence. The actual configuration of these identities are explained in detail in the Authentication Handbook.
Identity-based security policies are usually configured for IPSec or SSL VPN traffic since this type of traffic usually requires authentication from network users.