New Post: How to diffrentiate Device type in snmp

hi,
first thanks for this awesome library,

I am using Get method for retrieving device information.

i found below concept from internet : -

Switch :-
If the device is a Switch, it should respond for the OID ".1.3.6.1.2.1.17.1.2.0" and ".1.3.6.1.2.1.4.1.0" value will be 2.

Router:-
If the device is a Router, it should respond the OID ".1.3.6.1.2.1.4.1.0" value as 1.

Printer :-
If the device is Printer, it should respond for the OID ".1.3.6.1.2.1.43.5.1.1.1.1" .

Now, my problem is when i query 1.3.6.1.2.1.4.1.0 then it's returning 2 that's is switch (according to concept), but that is not a switch . it's actually other device like UPS or power transmission unit or modem.

in this condition how can i identify network device type ?

if there is any other way to find device type like server,workstation,router,switch,printer,smart phones, power transmission unit,bridge and so on.

Thanks in Advance.