[SNMP4J] need suggestion..

[Wenchun (Jackie) Cheng]

Hi to all,
 
Suppose I am implementing a high performance SNMP monitor application which
usess snmp v3 to poll several devices. And the snmp v3 users on the device
may not be using the same auth/priv passphrases. 
 
For example, 
on device group A,
the user is "snmpuser" and the auth/priv passphrases are
"passauth"/"passpriv".
 
on device group B,
the user is "snmpuser" and the auth/priv passphrases are
"authpass"/"privpass".
 
Since there is only one instance of SecurityModels to hold v3 user model, it
can only hold one generic (not associated with any authoritiveEngineID)
UsmUser with name "snmpuser". It seems like I can only add v3 user on the
fly, which means add the user before sending any snmp packet to the target.
Other than this method, can anyone suggest what the best way (or possible
way) to implement the system?
 
As a side question, what may be the reason to implement SecurityModels as a
singleton?
 
Thank you very much,
 
--Jackie