Cisco ISE is a technology that works with user identities by linking to an identity store (such as Active Directory), and based on these identities, along with device identity management, allows legitimate users and their devices to access the network. It ensures that users have access to the resources and data they should have access to and, conversely, that they do not have access where they should not.
It is an essential part of the 802.1X protocol implementation, which provides network segmentation - an essential security feature in a modern network. Using TACACS+, it can also control access to other network elements and granularly control the capabilities of authorized individuals and their activities on those elements.
It provides management and access for your guests through the Guest Portal. Your guests will have easy access to the Internet or to the data you specify, while maintaining security.