Which command indicates that SNMPv3 is being used?
SNMPv3 is identified by its user-based security model, which requires configuring SNMP users rather than community strings. On Cisco devices, snmp-server user creates an SNMPv3 user, so that command specifically implies SNMPv3. By contrast, snmp-server community is associated with SNMPv1/v2c, and the host/trap commands are not exclusive to SNMPv3.
snmp-server user
snmp-server community
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