This MIB extends the OID's for SNMP-USM-MIB specified in RFC 3414. 
        
The privacy protocol OID's specified herein are intended to be used as values for usmUserPrivProtocol when managing SNMPv3 users via the snmpUsmMIB. 
        
This MIB defines the OID's for the following encryption options: 
        
    * 256 bit key size AES 
        
OID for 128 bit key size AES encryption is defined in SNMP-USM-AES-MIB as per the RFC 3826.