Device sensor is a feature of access devices. It allows to collect information about connected endpoints. Mostly, information collected by Device Sensor can come from the following protocols:
+ Cisco Discovery Protocol (CDP)
+ Link Layer Discovery Protocol (LLDP)
+ Dynamic Host Configuration Protocol (DHCP)
Explanation Device sensor is a feature of access devices. It allows to collect information about connected endpoints. Mostly, information collected by Device Sensor can come from the following protocols: + Cisco Discovery Protocol (CDP) + Link Layer Discovery Protocol (LLDP) + Dynamic Host Configuration Protocol (DHCP) Reference: https://www.cisco.com/c/en/us/support/docs/security/identity-services-engine/200292-ConfigureDevice-Sensor-for-ISE-Profilin.html

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api_host=api.apjc.amp.cisco.com&api_resource=Computer&api_version=v1

A Directory Harvest Attack (DHA) is a technique used by spammers to find valid/existent email addresses at a domain either by using Brute force or by guessing valid e-mail addresses at a domain using different permutations of common username. Its easy for attackers to get hold of a valid email address if your organization uses standard format for official e-mail alias (for example: [email protected]). We can configure DHA Prevention to prevent malicious actors from quickly identifying valid recipients.
Note: Lightweight Directory Access Protocol (LDAP) is an Internet protocol that email programs use to look up contact information from a server, such as ClickMail Central Directory. For example, here's an LDAP search translated into plain English: "Search for all people located in Chicago who's name contains "Fred" that have an email address. Please return their full name, email, title, and description.