securityname is used by the NMS to identify devices that send traps.

SNMPv3 requires that securityname must be the same as the user name, and must be configured on both the device and NMS. The NMS can receive traps from a device only after passing the securityname verification (including authentication and encryption modes).

SNMPv1 and SNMPv2c do not require securityname verification; therefore, securityname can be different from the community name.

securityname is configured using the snmp-agent target-host trap, snmp-agent target-host inform or snmp-agent target-host trap ipv6 command.