When you think about identity management, what comes to mind? Probably things like LDAP directories, strong authentication, and Single Sign-On (SSO) systems. In general, these technologies are used for access to Windows networks, e-mail, and other internal applications. Of course, network pipes provide the actual infrastructure for these application layer communications, but network identity is far more elementary than application-layer activity. Generally, network identity is associated with things like IP and MAC addresses, VLAN tags, and subnets. It also plays a role in security in areas like device authentication, VPNs, and IPSEC.