Cisco Context Directory Agent (CDA) is a mechanism that maps IP Addresses to usernames in order to allow security gateways to understand which user is using which IP Address in the network, so those security gateways can now make decisions based on those users (or the groups to which the users belong to). CDA runs on a Cisco Linux machine; monitors in real time a collection of Active Directory domain controller (DC) machines for authentication-related events that generally indicate user logins; learns, analyzes, and caches mappings of IP Addresses and user identities in its database; and makes the latest mappings available to its consumer devices. Reference: https://www.cisco.com/c/en/us/td/docs/security/ibf/cda_10/Install_Config_guide/cda10/ cda_oveviw.html security gateways to understand which user is using which IP Address in the network, so those security gateways can now make decisions based on those users (or the groups to which the users belong to).
CDA runs on a Cisco Linux machine; monitors in real time a collection of Active Directory domain controller (DC) machines for authentication-related events that generally indicate user logins; learns, analyzes, and caches mappings of IP Addresses and user identities in its database; and makes the latest mappings available to its consumer devices.
Reference:
Cisco Context Directory Agent (CDA) is a mechanism that maps IP Addresses to usernames in order to allow security gateways to understand which user is using which IP Address in the network, so those security gateways can now make decisions based on those users (or the groups to which the users belong to). CDA runs on a Cisco Linux machine; monitors in real time a collection of Active Directory domain controller (DC) machines for authentication-related events that generally indicate user logins; learns, analyzes, and caches mappings of IP Addresses and user identities in its database; and makes the latest mappings available to its consumer devices. Reference: https://www.cisco.com/c/en/us/td/docs/security/ibf/cda_10/Install_Config_guide/cda10/ cda_oveviw.html

Because MAB uses the MAC address as a username and password, you should make sure that the RADIUS server can differentiate MAB requests from other types of requests for network access. This precaution will prevent other clients from attempting to use a MAC address as a valid credential. Cisco switches uniquely identify MAB requests by setting Attribute 6 (Service-Type) to 10 (Call-Check) in a MAB Access-Request message. Therefore, you can use Attribute 6 to filter MAB requests at the RADIUS server. Reference: https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/identity-based-networkingservices/config_guide_c17-663759.html identify MAB requests by setting Attribute 6 (Service-Type) to 10 (Call-Check) in a MAB Access-Request message. Therefore, you can use Attribute 6 to filter MAB requests at the RADIUS server.
Because MAB uses the MAC address as a username and password, you should make sure that the RADIUS server can differentiate MAB requests from other types of requests for network access. This precaution will prevent other clients from attempting to use a MAC address as a valid credential. Cisco switches uniquely identify MAB requests by setting Attribute 6 (Service-Type) to 10 (Call-Check) in a MAB Access-Request message. Therefore, you can use Attribute 6 to filter MAB requests at the RADIUS server. Reference: https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/identity-based-networkingservices/config_guide_c17-663759.html