This field contains a network mask that is logically ANDed with the IP address of the manager making an SNMP request. If the result of the logical AND is equal to the address specified in the address field and the community name matches, the request is processed.
To allow SNMP requests only from the host specified in the address entry field, specify a network mask of 255.255.255.255.
To allow any host with the correct community name to make SNMP requests, specify a network mask of 0.0.0.0 and an address of 0.0.0.0.