Port state in SNMP



I would like to check port states of a switch.
I have created a host for my switch and how can I do for the ports?

For I now I have created one host per port with a *parents *directive designing the switch.
But I have 196 ports so 196 host …

It works but is there another method ?
Is there a way that nagios get the ifNumber.0 and loop for all ports?

Than you